### Home > INT1 > Chapter A > Lesson A.1.5 > ProblemA-56

A-56.

Calculate the following values.

1. If $y = 2 + 4.3x$, what is the value of $y$ when $x = −6$?

Substitute −6 in for x.
y = 2 + 4.3( −6 )

Multiply and simplify.

y = 2 + (−25.8)

y = −23.8

2. If $g(x)=(x−3)^2$, what is the value of $g(−9)$?

Follow the steps in part (a).

Remember to use the correct order of operations.

3. If $C(x)=x−2$, what is the value of $x$ when $C(x)=3.5$?

Begin by substituting $3.5$ for $x$ in the equation.

4. If $y = 5x^{2} − 4$, what is the value of $y$ when $x = −2$?

Rewrite the equation as $y=5(−2)^2−4$.

$16$