Q. If 64x2+px+81=(8x+q)2, where p and q are positive constants, what is the value of qp ?
Expand equation: We have the equation: 64x2+px+81=(8x+q)2Expand the right side of the equation (8x+q)2 to get 64x2+16qx+q2.
Compare coefficients: Compare the coefficients of the corresponding terms on both sides of the equation. We have 64x2 on both sides, so they match. Now, compare the linear term and the constant term. We have px on the left side and 16qx on the right side, so p=16q. For the constant terms, we have 81 on the left side and q2 on the right side, so q2=81.
Find q: Since q2=81 and q is a positive constant, we take the positive square root of 81 to find q. Therefore, q=9.
Find p: Substitute q=9 into the equation p=16q to find the value of p. So, p=16×9=144.
Calculate qp: Now that we have both p and q, we can find the value of qp. So, qp=9144. Simplify the fraction9144 to get the final value of qp. Therefore, qp=16.
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