Answer
x=2
ST=18
MN=9
Work Step by Step
ST=2(MN)
x(2x+5)=2(x$^{2}$+5)
2x$^{2}$+5x=2x$^{2}$+10
5x=10
x=2
ST=2x$^{2}$+5x
ST=2(2)$^{2}$+5(2)
ST=8+10=18
MN=x$^{2}$+5
MN=4+5=9
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.