Question

If C = x2 + 7 and D = 3x2 - 4x + 3, find an expression that equals 3C + 3D in standard form.​

Answer 1

The new expression is: 12 x^2 - 12 x+ 30

Explanation:

if C = x^2 + 7

and

D = 3 x^2 - 4 x + 3

Then, 3 C + 3 D can be obtained via:

3 ( x^2 + 7 ) + 3 ( 3 x^2 - 4 x + 3 ) = 3 x^2 + 21 + 9 x^2 - 12 x + 9 =

= 12 x^2 - 12 x+ 30