Can someone me simplify this answer i keep getting it wrong?

The answer is -8

I found my answer by using desmos. It is the best app for graphing. I wrote the equation and then I looked for the point 18 on the y axis and then I looked where it was on the x axis

that is how I found my answer.

so firstly, we need to isolate the y variables to be able to solve these inequalities. firstly, add 0.5x on both sides of the first inequality and subtract 1.5x on both sides of the second inequality:

now since the slope is positive for the first inequality, this means that the line going upwards belongs to the first inequality, and the line going downwards belongs to the second inequality.

next, since y ≥ in the first inequality, this means that the shaded region will be above the first inequality's line, thus shading regions a and b.

next, since y ≤ in the second inequality, this means that the shaded region is going to be below this line, thus shading regions a and c.

since both lines shade region a, this means that region a is the solution.

step-by-step explanation:

mark brainliest!

i believe your answer is 99.7% of 7-year-old children are between 46.6 inches and 49.5 inches tall.