So, put your "x's" together first and then your intercepts. That should answer your question :)
Second option, just do Pemdas backwards.
The square root of 80 can be broken up into the square root of 16 x square root of 5. We know that the square root of 16 is 4. So in the form (a sqrt b)
A would be 4 and b would be 5.
Answer: 4 sqrt 5
The dimensions that would result to maximum area will be found as follows:
let the length be x, the width will be 32-x
thus the area will be given by:
P(x)=x(32-x)=32x-x²
At maximum area:
dP'(x)=0
from the expression:
P'(x)=32-2x=0
solving for x
32=2x
x=16 inches
thus the dimensions that will result in maximum are is length=16 inches and width=16 inches
Given:
To find:
The obtuse angle between the given pair of straight lines.
Solution:
The slope intercept form of a line is
...(i)
where, m is slope and b is y-intercept.
The given equations are
On comparing these equations with (i), we get
Angle between two lines whose slopes are 
is
Putting and , we get
Now,
and 
and 
and 
, so it is an obtuse angle and 
, so it is an acute angle.
Therefore, the obtuse angle between the given pair of straight lines is 120°.
