Question

Evaluate each expression if $a=-2,b=-3,c=2$, $x=2.1,y=3$, and $z=-4.2$.

$-a+\left|2x-a\right|$

Short answer

The expression$-a+\left|2x-a\right|$ is equal to 8.2.

Step-by-step solution

Step-1. Define absolute value expression.

Absolute values define an upper and lower range in which a value must lie.

Step-2. Substitute the variables.

In order to evaluate the expression $-a+\left|2x-a\right|$ substitute -2 for a, -3 for b, 2 for c, 2.1 for x, 3 for y and -4.2 for z.

$-a+\left|2x-a\right|=-\left(-2\right)+\left|2\times 2.1-\left(-2\right)\right|$

Step-3. Simplify the expression.

Solve the expression as per order of operations.

$$\begin{gathered} -a+\left|2x-a\right|=-\left(-2\right)+\left|2\times 2.1-\left(-2\right)\right| \\ =2+\left|2\times 2.1+2\right| \\ =2+\left|4.2+2\right| \\ =2+\left|6.2\right| \\ =2+6.2 \\ =8.2 \end{gathered}$$

Therefore, the value expression is 8.2.