<span>the formula that I used would be
p = a √( 2 - 2 cos(A) ) = a √( 2 + 2 cos(B) )q = a √( 2 + 2 cos(A) ) = a √( 2 - 2 cos(B) )<span>p2 + q2 = 4a2
this would give us these measurements for the diagonals
p=9
q=15</span></span>
You multiply 2 and 2, and then divide it by 5
24.5= <span><span>−<span>2.5c</span></span>−<span>4<span>c
</span></span></span><span>24.5=<span><span><span>−<span>2.5c </span></span>+ </span>−<span>4c</span></span></span><span>24.5 = <span>(<span><span>−<span>2.5c</span></span>+<span>−<span>4c</span></span></span>) </span></span><span>24.5=<span>−<span>6.5c </span></span></span><span>24.5=<span>−<span>6.5<span>c
</span></span></span></span><span>−<span>6.5c</span></span>=<span>24.5
</span><span><span><span>−<span>6.5c </span></span><span>− 6.5 </span></span>=<span>24.5 <span>− 6.5 </span></span></span><span>c=<span>−<span>3.769231
These are all the steps that you do to solve this equation. I worked it out fully and the answer is above these words.</span></span></span>
"<span>Start by setting up the standard equation for perimeter of a parallelogram, P=2w+2h (these variables of course being width and height). </span>
Now, substitute in what you know...
<span>The problem tells us that width is equal to height minus four. This means that, in order to keep only one variable in this problem, we will write width as h-4. </span>
<span>The problem also tells us that 72 is the perimeter, so we substitute that for P. </span>
72=2(h-4)+2h
<span>Now solve from here. </span>
<span>(Distribute first) </span>
72=2h-8+2h
(Combine like terms)
72=4h-8
80=4h
(Isolate h)
80/4=h
<span>20=h"</span>
