Answer:
The correct answer is,
he value of expression 7x(3x+x)when x is 8= 1792
Explanation:
It is given expression is,
7x(3x+x)
Simplify 7x(3x+x)
7x(3x+x) =7x ( 4x)
= 28x²
To find the value of 7x(3x+x) when x = 8
7x(3x+x) = 28x²
x = 8
28x² = 28 * 8² = 28*64 = 1792
Therefore the value of 7x(3x+x)when x is 8 = 1792