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Tuesday, November 30, 2010
Math Pages 125-127
-Means out of 100
-Another name for hundredths
-65% means 65 out of 100 or 65/100 or 0.65
Fractional Percent:
-A percent that includes a portion of a percent such as 7 3/8% or 4.5%
Page 125 Show you Know
A) 248%=
B) o.4%=
C) 74.8%=
Page 127 Show you Know
A)
B)
C)
Thursday, November 18, 2010
Duyen's Math Scribe Post: Pages 110 & 111 Questions 3, 9, 13
Sorry for the bad quality because when I converted the PowerPoint to AuthorStream then to Youtube, it just killed the original quality. Also if you notice the words might seem squished or cut well it's not. It's just that when AuthorStream converted the file it converted it to make it fit to a smaller screen. By the way it's suppose to have music, but it didn't work on Authorstream.
Watch
http://www.youtube.com/watch?v=iFPsqk8MYj0
http://www.youtube.com/watch?v=FUhpIS8YTfc
http://www.youtube.com/watch?v=ku4rEwRxZOc
http://www.youtube.com/watch?v=kBw_i6tlQfU
Play
http://www.quia.com/jg/65631.html
http://resources.oswego.org/games/
Search
http://www.mathsisfun.com/square-root.html
http://staff.argyll.epsb.ca/jreed/math8/strand1/1105.htm
Paulo's Textbook Post page 110-111 numbers 3 7 11
Wednesday, November 17, 2010
Raelynn's Homework Book Post: pg. 33 Numbers 4,6,7
Homework Book pg. 33
Numbers 4, 6, 7.
4.) The foot of a ladder is 1m from a wall. If the ladder is 6cm long, how far up the wall does the ladder reach? Give the answer to the nearest tenth of a metre. Show your work.
a² - b² = c²
6² - 1² = c²
(6x6) - (1x1) = c²
36cm² - 1cm² = 35 cm²
35cm² = c²
√35cm² = √c²
5.9cm² = c² (round up will be 6)
It will be 5.9/6 far up the wall.
6.) The width of a rectangle is 8cm, and its diagonal is 17cm.
a) Calculate the length of the rectangle. Show your work.
c² - b² = a²
17² - 8² = a²
(17x17) - (8x8) = a²
289cm² - 64cm² = 225cm²
225cm² = c²
√225cm² = √c²
15cm² = c²
b) Calculate the area of the rectangle.
120cm²
7.) A quadrilateral has a width of 17cm and a length of 26cm. A diagonal is 31cm. Is the quadrilateral a rectangle? Justify your answer.
a² + b² = c²
26² + 17² = c²
(26x26) + (17x17) = c²
676cm² + 289cm² = 965cm²
965cm² = c²
√965cm² = √c²
31.06cm²
Answer: No, the corners do not meet at right angles because 17² + 26² ≠ 31²
Enjoy this video. Hope it helps.
Tuesday, November 16, 2010
Shane's Textbook Post Pages 103-105. Numbers 7,10,13,15
a.)
h² + 5² = 9²
h² = 9² - 5²
h² = (9x9) - (5x5)
= 81-25 = 56
= √h² = √56 mm²
= h = 7.48 mm
p² + q² = r²
p² + 11² = 15²
p² = 15² - 11²p
p² = (15x15) - (11x11)
= 225 - 121 = 104
= √p² = √104 mm²
= 10.20
a² + b² = c²
27 m² + 27 m² = c²
(27x27) + (27x27)
729 + 729 = c²
1458 m²
√1458 m² = √c²
38.18 m²
a² + b² = c²
8² + b² = 10 mm
b² = 10² - 8²
b² = (10x10) - (8x8)
= 100 - 64 = 36
= √b² = √36 mm²
= b = 6 mm
a² + b² = c²
=22 + 42 = c²
=4 + 16 = c²
=20 = c²
The square root of 20 = c²
c² = 4.47
Homework Book : Even Questions
a² = 26² - 24²
a² = 676 - 576
a² = 100m²
√100m² = √a²
10m = a
b) b² = c² - a²
b² = 39² - 15²
b² = 1521 - 225
b² = 1296cm²
√1296cm² = √b²
36cm = b
a) a² + b² = c²
8² + 9² = c²
64 + 81 = c²
145cm² = c²
√145cm² = √c²
12cm = c
b) a² + b² = c²
6² + 10² = c²
36 + 100 = c²
136cm² = c²
√136cm² = √c²
12cm = c
I thought of the height as the line going upwards↑, the base as the bottom_, and the hypotenuse is the longest leg. I used B as the unknown height.
b² = c² - a²
b² = 11² - 4²
b² = 121 - 16
b² = 105cm²
√b² = √105cm²
b = 10.2m
No the ramp is not a right triangle because the areas of the legs added up to 13m². The area of the hypotenuse on the other hand was 25m². For the shape to be a right triangle the two values would have to be equal.
Here is a video and a link to a fun-filled Pythagoras game. ←Click that for the game ☺
P.S if you see a √ its a square root symbol.
Trisha's Textbook pages (:
# 6, 9, 12 and 15
6. Determine the length of the leg for each right triangle.
a)
a2 + b2 = c2
72 + 252 = c2
49 + 625 = c2
674 =c2
The square root of 674cm = c2
25.96 cm = c
b)
T2 - S2 = R2
262 - 242 = R2
676 - 576 =R2
100 = R2
10cm = R2
9. Tina wants to construct a path along the diagonal of her yard. What length will the path be? Express your answer to the nearest tenth of a meter.
a2 + b2 = c2
62 + 122 = c2
36 + 144 = c2
180 = c2
The square root of 180 = c2
13.41 = c
12. The hypotenuse of the triangle cuts the circle in half. What is the diameter of the circle?
a2 + b2 = c2
72 + 52 = c2
49 + 25 = c2
74 = c2
The square root of 74 = c2
8. 60
15. The coordinate grid shown was drawn centimeter grid paper. What is the length of lime segment AB?
A and B segment looks like a right triangle.
a2 + b2 = c2
22 + 42 = c2
4 + 16 = c2
20 = c2
The square root of 20 = c2
4.47 = c
Special thanks to Anabelle for helping me out (:
Thanks.
Patrick's Textbook Post Pages 103-105. Numbers 5,8,11,14
area of square = a²
area of square = 6x6
area of square = 36cm²
Homework Book: Odd Questions
of a right triangle when the lengths of the two_______ are known.
pythagorean, lengths, hypotenuse, legs
3)Determine the length of each hypotenuse.show your work.
A)
a²+b²=c²
9cm²+40cm²=c²
9x9+40x40=c²
81cm²+1600cm²=c²
1681cm²=c²
√1681cm²=√c²
41cm=c
B)
a²+b²=c²
12m²+35m²=c²
12x12+35x35=c²
144m²+1225m=c²
1369m²=c²
√1369m²=√c²
37m=c
5)Calculate the missing side length for each right triangle, to the nearest tenth of a centimetre. Show your work.
A)
c²-a²=b²
6cm²-5cm²=b²
6x6+5x5=b²
36cm²+25cm²=b²
11cm²=b²
√11cm²=√b²
3.3cm=b
B)
c²-b²=a²
12cm²-7cm²=a²
12x12+7x7=a²
144cm²+49cm²=a²
95cm²=a²
√95cm²=√a²
9.7cm=a
7)A triangle is made up of two smaller congruent right triangles.
A)Find the length of the hypotenuse for the right triangles, to the nearest tenth of a metre. Show your work.
a/2=a²
8/2=4
a²+b²=c²
4²+2²=c²
4x4+2x2=c²
16m²+4m²=c²
20m²=c²
√20m²=√c²
4.5m=c
B)Calculate the perimeter of the large triangle, to the nearest tenth of a metre. Show your work.
a+b=perimeter
8+4.5=17 m
Here is a link about Pythagorean Relationship.
Here is a video using math link textbook about pythagorean relationship.
Monday, November 15, 2010
Finding Side Lengths
from second base to home plate? How many different strategies can
you develop?Determine the length of leg s of the
right triangle
p2 + q2 = r2
p2 + 122 = 152
p2 + 144 = 225
p2 + 144 - 144 = 225 - 144
p2 = 81
p = √
___
81
p = 9
169y2 = 194y2
Give your answer to the nearest tenth of
a centimetre.
85 square rooted=9.2