Angie Applegate has a photograph for which the length is 2 inches longer than the width. If she increases each dimension by 4 inches, the area is increased by 88 square inches. How do you find the original dimensions?

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Answer 1 · 2017-08-03T06:31:07

$8"in" xx 10"in"$

At first you have $x(x+2)=a$ , and after, you have $(x+4)(x+6)=a+88$

By expanding the brackets you get $x^2+10x+24=a+88$

By putting all terms onto one side, you get $x^2+10x-64=a$

$x^2+10x-64=a$
$x^2+2x=a$

$x^2+10x-64=x^2+2x$

$8x-64=0$

$8x=64$

$x=64/8=8$

$8(8+2)=8*10=80$
$(8+4)(8+6)=12*14=168$
$168-80=88$

$x=8"in"$
$x+2=8+2=10"in"$

$8"in" xx 10"in"$