The answer is A( +7) x (-5)
(x+y=31)2
2x-y=11
2x+2y=62
- 2x -y=11
3y=51
y=17
x+17=31
x=14
y-x=3
If you know the base and area of the triangle, you can divide the base by 2, then divide that by the area to find the height. To find the height of an equilateral triangle, use the Pythagorean Theorem, a^2 + b^2 = c^2.
0.89
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