Question

The surface area for a rectangular prism is given by the formula SA = 2ab + 2bc + 2ac, where a, b, and c are the lengths of the prism.

If the surface area of a rectangular prism with side c measuring 11 meters is 270 square meters and length of side a measuring the same length as side b, then what is the length of side a of the rectangular prism?

Answer 1

a = 5 meters

Explanation:

You are given:

2ab + 2bc + 2ac=270 which also equals ab+ bc+ ac= 135

Since you are given a=b and c=11 we can sub in those values

a^2 + 11a + 11a= 135 or a^2 + 22a - 135

(You can substitute every "b" with "a" and every "c" with "11").

Then you can solve this quadratic equation for its solutions, either by factoring or grouping {also tip for these kinds of quadratic solutions you can input it on photo math if you realllyyyy don't want to solve it}

Afterwards, your results are x= -27 and x=5; since -27 doesn't make sense as a length your answer is 5