Answer:
x ≈ 4.5
Explanation:
First, use the Pythagorean theorem to find the missing variable with side 8 and hypotenuse 10.
a² + b² = c²
a² + 8² = 10²
Square the variables
a² + 64 = 100
Subtract 64 from both sides.
a² = 36
Take the square root of both sides.
a = 6.
Now we can find the other triangle and we now know that one side is 4 and the hypotenuse is 6.
a² + b² = c²
x² + 4² = 6²
Square the variables.
x² + 16 = 36
Subtract 16 from both sides.
x² = 20
Square root. (refresh if you don't see this part.)
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Converted to decimal to the nearest tenth, the answer is
x = 4.5.
Now let's prove it.
