Answer:
Starting with ΔABC, draw the dilation image of the triangle with a center at the origin and a scale factor of two. Notice that every coordinate of the original triangle has been multiplied by the scale factor (x2). Dilations involve multiplication! Dilation with scale factor 2, multiply by 2.
Because 1/2 of 6 =1/3 and 1/2×1/3=1/6
11. 5x^2-30=0
+30 to both sides
5x^2=30
÷5 both sides
x^2=6
square root both sides
x= +square root 6 ,- square root 6
12. 4x^2+10=26
-10 both sides
4x^2=16
÷4 both sides
x^2=4
square root both sides
x=+2,-2
13. a=72yrd^2
l=2w
w=?
a=l×w
72=2w×w
72=2w^2
÷2 both sides
36=w^2
square root both sides
w=+6,-6
a measurement can't be - so w=6
Plug into l=2w
l=2×6
l=12
w=6
Answer: Choice C) {6, 9, 12}
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Explanation:
Something like choice A can't form a triangle because the first two sides add to 6+9 = 15, which is <u>not</u> longer than the third side 15. We need to have x+y > z to be true. The same goes for choice B as well because 3+3 = 6 is too small compared to the third side 7. Choice D is similar to choice A.
In short, we can rule out choices A, B, and D.
The only thing left is choice C. Picking any two sides leads to having that sum be larger than the third side
- 6+9 = 15 which is larger than 12
- 9+15 = 24 which is larger than 6
- 6+15 = 21 which is larger than 9
So the conditions of the triangle inequality theorem work out here, and we have a triangle.