Answer:
√21 or 4.58
Step-by-step explanation:
area of triangle can be found in different ways, and they are equal as:
1/2*x*(7+3)= 1/2*√(x²+3³)*√(x²+7²)
(10x)²= (x²+3³)*(x²+7²)
x²= y
- 100y= (y+9)(y+49)
- y²+58y+9*49-100y=0
- y²-42y +441=0
- y=21
x²=21
x=√21 = 4.58
