Step-by-step explanation:
x²-y²=12
(x-y)(x+y)=12
but x-y=4
4(x+y)=12
x+y=12/4
x+y=3
lets make x the subject of the formula
x=3-y
since x-y=4
(3-y)-y=4
3-y-y=4
-2y=1
y=-1/2
then x=3-y
x=3-(-1/2)
x=(6--1)/2
x=7/2
therefore; x²+2xy+y
=(7/2)²+2×7/2×-1/2+(-1/2)
=49/4-7/2-1/2
=(49-14-2)/4
=33/4
=8.25
=8 
 
        
             
        
        
        
Answer:
$4,316
Step-by-step explanation:
Semester one: $166 per credit times 13 hours = $2,158
Semester two: $166 per credit times 13 hours = $2,158
Cost for semester one plus semester two = $4,316
 
        
             
        
        
        
In the the figure above AC bisects BCD in the quadrilateral, the length of CD will be 6cm.
<h3>How to calculate the value?</h3>
It should be noted that the longer diagonal is a perpendicular bisector of the shorter diagonal.
From the diagram given, the value of AD is 6cm. Therefore, according to the angle bisector theorem, the value of CD is 6cm as they're congruent.
Learn more about quadrilateral on:
brainly.com/question/23935806
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