## Algebra 1

$25x^2(9-\pi)$
The area of the metal portion of the frame is the total area reduced by the area taken up by the mirror. The total area inside the frame is $l\times w=15x\times15x=225x^2$ The area of the circular mirror is $\pi r^2=\pi(5x)^2=25\pi x^2$ The area of the metal portion of the frame is the total area reduced by the area taken up by the mirror. $225x^2-25\pi x^2$ Find the greatest common factor of the terms. Find the prime factors of each term. Multiply the common factors to find the GCF. $225x^2=\underline5\times\underline5\times9\times\underline x\times\underline x$ $25\pi x^2=\underline5\times\underline5\times\pi \times\underline x\times\underline x$ GCF$=5\times5\times x\times x=25x^2$ Factor the GCF out of each term. Use the factors that were not part of the GCF. $225x^2-25\pi x^2=25x^2(9-\pi)$