We have x^2 + 2 · x · (11/2) + (11/2)^2 = - 24 + (11/2)^2;
Then, ( x + 11/2 )^2 = -24 + 121/4;
( x + 11/2 )^2 + 96/4 - 121/4 = 0;
( x + 11/2 )^2 - 25 / 4 = 0;
( x + 11/2 )^2 - (5/2)^2 = 0;
( x + 11/2 - 5/2)·( x + 11/2 + 5/2 ) = 0;
( x + 6/2 )·( x + 16/2 ) = 0;
( x + 3 )· ( x + 8 ) = 0;
x = - 3 or x = -8;
The first choice is the correct answer.
A number x minus a number y multiplied by 5
It's a bit of a bummer to have to work through all of these to find the answer. That a lot of slope calculations (or graphing, or whatever). When there are this many, a spreadsheet or other machine help can make it easier.
The correct choice is the last one, XYZ, with vertex X being where the right angle is located.
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Slope of XY is 4/7; slope of XZ is -7/4. The product of these is -1, so those segments are at right angles.
160 feet long most likely