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I don’t understand these 3 questions and I need help.

I don’t understand these 3 questions and I need help.-example-1
User Aakpro
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2 Answers

7 votes
Not sure about the first one but the second one is option c (or -3). You just have to factor and find the solutions (so it would be -7 and 4 and then u just add them)

For question 39 the answer is c
User Slava Dobromyslov
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4.8k points
1 vote

Answer:

1: A=1

2: -3

3: C

Explanation:

1: If 3x+4 is a factor, then -4/3 is equal to x. Substitute it in for x and solve for a. This gives us A=1.

For the commenter not understanding how I got -4/3: 3x+4 being a factor means that it equals 0. It might help you understand this if you remember that after factoring, like I did for 38 in my photo, we take expressions like x-4 and set them equal to 0 to get x=4, a solution. So, subtract 4 from both sides to get 3x=-4, then divide both sides by 3 to get x alone. Thus, x=-4/3.

2: To find the sum, we first need to find the two solutions. We can factor to get (x+7)(x-4). This gives us x=-7 and x=+4. The solution of these two would be (-7)+4 is -3.

3: B is a close answer, but the signs are wrong on the bottom. Factoring the question would give us 2(x-2) / 2(x^2-x-2). Factoring that equation is 2(x-2) / 2(x+1)(x-2). Simplifying this gives us 1 / x+1.

Sorry for the bad penmanship, I wanted to make it a little clearer for you! I really hope I helped! :)

I don’t understand these 3 questions and I need help.-example-1
User Khandad Niazi
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4.0k points