SOLUTION: A wooden frame surrounds a 5 inch by 7 inch photograph. The frame is the same width all the way around. How wide is the frame if it has an area of 32 square inches?

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Question 800361: A wooden frame surrounds a 5 inch by 7 inch photograph. The frame is the same width all the way around. How wide is the frame if it has an area of 32 square inches?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
I can say:
+%28+5+%2B+2x+%29%2A%28+7+%2B+2x+%29+-+5%2A7+=+32+
+35+%2B+14x+%2B+10x+%2B+4x%5E2+-+35+=+32+
+4x%5E2+%2B+24x+-+32+=+0+
+x%5E2+%2B+6x+=+8+
Complete the square
+x%5E2+%2B+6x+%2B+%286%2F2%29%5E2+=+8+%2B+%286%2F2%29%5E2+
+x%5E2+%2B+6x+%2B+9+=+8+%2B+9+
+%28+x+%2B+3+%29%5E2+=+sqrt%2817%29%5E2+
+x+%2B+3+=+sqrt%2817%29+
+x+=+sqrt%2817%29+-+3+
+x+=+4.123+-+3+
+x+=+1.123+
The frame is 1.123 inches wide
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check:
+%28+5+%2B+2x+%29%2A%28+7+%2B+2x+%29+-+5%2A7+=+32+
+%28+5+%2B+2%2A1.123+%29%2A%28+7+%2B+2%2A1.123+%29+-+5%2A7+=+32+
+%28+5+%2B+2.246+%29%2A%28+7+%2B+2.246+%29+-+5.7+=+32+
+7.246%2A9.246+-+35+=+32+
+66.997+=+67+
close enough