Question

Solve 2(4x - 1) = -26, then use the value of x to evaluate 7x^2

Answer 1

Given:

The equation is given as,

`2(4x-1)=-26_{}`

The objective is to find the value of x and evaluate 7x².

Step-by-step explanation:

The value of x can be calculated as,

`\begin{gathered} 2(4x-1)=-26 \\ 8x-2=-26 \\ 8x=-26+2 \\ 8x=-24 \\ x=(-24)/(8) \\ x=-3 \end{gathered}`

To find 7x²:

The value of 7x² can be calculated as,

`\begin{gathered} 7x^2=7\cdot x\cdot x \\ =7(-3)\cdot(-3) \\ =7(9) \\ =63 \end{gathered}`

Hence, the value of x is -3 and the value of 7x² is 63.