Perform the indicated operation: $- 3 x ^ { 4 } y \left( 5 x ^ { 3 } y ^ { 2 } - 7 x \right)$
A) $- 15 x ^ { 7 } y ^ { 3 } + 21 x ^ { 5 } y$
B) $- 15 x ^ { 7 } y ^ { 3 } - 21 x ^ { 5 } y$
C) $6 x ^ { 6 } y ^ { 3 }$
D) $- 15 x ^ { 12 } y ^ { 2 } + 21 x ^ { 4 } y$

Question

Quizplus · Accepted Answer

When multiplying polynomials, you multiply the coefficients and add the exponents of like bases. For the first term: $-3x^4y * 5x^3y^2 = -15x^{4+3}y^{1+2} = -15x^7y^3$. For the second term: $-3x^4y * -7x = 21x^{4+1}y = 21x^5y$.

Perform the Indicated Operation −3x4y(5x3y2−7x)- 3 x ^ { 4 } y \left( 5 x ^ { 3 } y ^ { 2 } - 7 x \right)−3x4y(5x3y2−7x)

Perform the Indicated Operation $- 3 x ^ { 4 } y \left( 5 x ^ { 3 } y ^ { 2 } - 7 x \right)$