ok guys I need your help on this one>>> the dimensions of a rectangle are such that its length is 7inches more than it's width. If the length were doubled, and if the width were decreased by 3 inches. The area would be increased by 168 inches sq. What are the length and width of the rectangle? thanks guys
put x = width, then x +7 is the length and area is \[x(x+7)\]
ok then it all goes downhill from there lol
double the length, incraese the width by 3, get \[(x+3)\times 2(x+7)\]
and so you know that \[x(x+7)+168=2(x+3)(x+7)\]
now we solve the quadratic equation
ok x^2 +7x +168=2x+6+x+7
except i get a really ugly solution, so maybe i made a mistake
lol well join the club
oh because it said "decreased" if only i could read
\[x(x+7)+168=2(x-3)(x+7)\]
im getting all kinds of wierd answers on this one I cant match it on my check equation
\[x (x+7)+168 = 2 x^2+8 x-42\] \[x^2+7 x+168 = 2 x^2+8 x-42\] \[x^2+x-210 = 0\] \[(x+15)(x-14)=0\] \[x=14\]
are you for certain certain?????????????????????????
yes it matches mine. thanks
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