Answer:
9
Explanation:
The left side of the triangle is 20 units long, the bottom portion is 8 units long.
This means the top portion must be 12 units long, 20 - 8 = 12.
The ratio between the left and right side has to be the same because they are two straight lines.
So if the ration is 8 to 6 or 8/6 which reduces to 4/3 then your ration is 12 to x.
So if... 4/3x=12 then
(3)4/3x = 12(3) multiply both sides by 3
4x = 36 the divide both sides by 4
x = 9
To check you can multipy your answer, in this case 9 by 4/3.
(9)(4/3) =
(9 x 4)/3 =
36/3 = 12
You did it! Hope this helped.