A) 3= x + 7 b) -7a-49

Mathematics

2 answers:

xxTIMURxx [149]2 years ago

8 0

Answer:

A: x = -4

B: a = -7 (I'm assuming the '-' in front of 49 was supposed to be an '=')

Step-by-step explanation:

A: You need to group the like terms together, and isolate the variable, which in this case is x.

Take the 7 over to the other side, so the equation looks a little bit like this.

3-7 = x.

3-7 is -4, so we've gotten our answer.

x = -4.

B: -7a = 49.

When two negative numbers are multiplied together, the product becomes positive.

49 is 7x7.

-7 times -7 would be 49.

So, in this situation, a would be -7.

a = -7.

mars1129 [50]2 years ago

3 0

Answer: b im pretty sure hope this helps :)

Step-by-step explanation:

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spin [16.1K]

Answer:

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8 0

3 years ago

HELP PLEASE I'M WRITING A TEST!!!<br> x+3/4 = x+5/6

Keith_Richards [23]

Answer:

no solution

Step-by-step explanation:

if u plug a random number like 1 for example 1+3/4=1 3/4 and 1+5/6=1 5/6

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so no solution

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5 0

3 years ago

-1(x+5)=3[x+(2x-1)]<br> solved and justified each step

madreJ [45]

Answer:

Step-by-step explanation:

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