A rectangular picture frame is 5 inches wide and 10 inches tall. You want to make the area 6 times as large by increasing the length and width by the same amount. Find the number of inches by which each dimension must be increased.
Q. A rectangular picture frame is 5 inches wide and 10 inches tall. You want to make the area 6 times as large by increasing the length and width by the same amount. Find the number of inches by which each dimension must be increased.
Calculate original area: Original area of the frame is 5 inches ×10 inches.Calculate the original area: 5×10=50 square inches.
Calculate new area: The new area should be 6 times the original area.Calculate the new area: 6×50=300 square inches.
Find new dimensions: Let x be the number of inches to increase both the length and width.The new dimensions will be (5+x) inches by (10+x) inches.
Set up new area equation: The new area is (5+x)×(10+x).Set up the equation for the new area: (5+x)(10+x)=300.
Expand and simplify equation: Expand the equation: 50+5x+10x+x2=300. Simplify the equation: x2+15x+50=300.
Set equation to zero: Subtract 300 from both sides to set the equation to zero: x2+15x+50−300=0.Simplify the equation: x2+15x−250=0.
Factor quadratic equation: Factor the quadratic equation: (x+25)(x−10)=0.
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