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brilliants [131]

3 years ago

11

Find the missing coefficient. (5d-7)(5d-6)=25d^2+__d+42

2 answers:

krok68 [10]3 years ago

6 0

Answer:

$-65$

Step-by-step explanation:

$(5d-7)(5d-6)$

$5d(5d)+5d(-6)-7(5d)-7(-6)$

$25d^2+-30d+-35d+42$

$25d^2+-65d+42$

The missing coefficient of $d$ is $-65$ .

andrezito [222]3 years ago

6 0

Answer:

25d^2 -65d +42

Step-by-step explanation:

(5d-7)(5d-6)=25d^2+__d+42

FOIL

(5d-7)(5d-6)=

First 5d*5d = 25d^2

Outer 5d*-6 = -30d

Inner -7*5d = -35d

Last = -7*-6 = 42

Add them together

25d^2 -30d -35d +42

25d^2 -65d +42

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