Question 87191
1) HEIGHT=8 INCHES, LENGTH=W+3 INCHES, WIDTH=W.
VOLUME =L*W*H
560=(W+3)*W*8
560=(W^2+3W)*8
560/8=W^2+3W
70=W^2+3W
W^2+3W-70=0
(W+10)(W-7)=0
W+10=0
W=-10 NOT AN ANSWER.
W-7=0
W=7 ANSWER.
PROOF
560=(7+3)*7*8
560=10*7*8
560=560
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2) 1568=S^2
S=SQRT1568
S=39.597979 IS THE LENGTH OF THE SIDES.
THUS THE RADIUS IS S/2
39.597979/2=19.798989 FEET.
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3) SQRT(X^2+Y^2)
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4)AREA=S^2 & PERIMETER=4S. THUS:
S^2=4S+117
S^2-4S-117=0
(S-13)(S+9)=0
S-13=0
S=13 ANSWER.
PROOF
13^2=4*13+117
169=52+117
169=169