Multiply:
[−3d + (−7f)] by (5d + f)

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Solution

To multiply, we will use distributive law as follows:

$[- 3 d + (- 7 f)] (5 d + f) = (- 3 d) (5 d + f) + (- 7 f) (5 d + f) = (- 15 d^{2} - 3 d f) + (- 35 d f - 7 f^{2}) = - 15 d^{2} - 3 d f - 35 d f - 7 f^{2} = - 15 d^{2} - 38 d f - 7 f^{2}$

Thus, the answer is $- 15 d^{2} - 38 d f - 7 f^{2}$ .

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Multiply: [−3d + (−7f)] by (5d + f)

To multiply, we will use distributive law as follows: -3d+-7f5d+f=-3d5d+f+-7f5d+f=-15d2-3df+-35df-7f2=-15d2-3df-35df-7f2=-15d2-38df-7f2 Thus, the answer is -15d2-38df-7f2.

Multiply:
[−3d + (−7f)] by (5d + f)

To multiply, we will use distributive law as follows:

$[- 3 d + (- 7 f)] (5 d + f) = (- 3 d) (5 d + f) + (- 7 f) (5 d + f) = (- 15 d^{2} - 3 d f) + (- 35 d f - 7 f^{2}) = - 15 d^{2} - 3 d f - 35 d f - 7 f^{2} = - 15 d^{2} - 38 d f - 7 f^{2}$

Thus, the answer is $- 15 d^{2} - 38 d f - 7 f^{2}$ .