Answer:
x=28
Step-by-step explanation:
We can use similar triangles and proportions to solve this problem. Put the side of the small triangle over the same side of the larger triangle.
x 42
---------- = ----------
x+10 42+15
Simplify
x 42
---------- = ----------
x+10 57
Using cross products
57x = 42 (x+10)
Distribute
57x = 42x+420
Subtract 42x from each side
57x-42x = 42x-42x +420
15x = 420
Divide each side by 15
15x/15 = 420/15
x=28
A = (h * b) / 2
A = 200
h = 4b
200 = (b(4b) / 2
200 * 2 = b * 4b
400 = 4b^2
400 / 4 = b^2
100 = b^2
sqrt 100 = b
10 = b ..... base is 10 cm
h = 4b
h = 4(10)
h = 40 <=== height is 40 cm
The
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symbol means intersection, so everything that is in both sets, and the
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symbol means union, so the two sets combined.
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So the answer is A.
-5- is the correct answer
The same as the last question. B the second option.