what are a and b is a+3b=-3 and 2b=a-12.

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We have the following equations to solve for a and b:

a+3b=-3...(1)

2b=a-12...(2)

Adding (1) and (2)

=> a + 3b + 2b = -3 + a - 12

=> 5b =-15

=> b = -3

substituting this in (2)

=> -6 = a - 12

=> a = 12 - 6

=> a = 6

Therefore a = 6 and b = -3.

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An illustration of the letter 'A' in a speech bubbles

Given the equations:

a + 3b = -3 ..............(1)

2b = a -12

==> -a+2b = -12 ............(2)

We have a system of two equations and two variables.

Then, we will use the elimination method to find a and b.

==> We will add (1) + (2).

==> 5b= -15

Now we will divide by 5.

==> b = -15/5 = -3

==> b= -3

Now we will substitute into (1) to find a.

==> a + 3b = -3

==> a + 3(-3) = -3

==> a -9 = -3

==> a = 9-3 = 6

==> a = 6

Then, the answer is:

a = 6   and   b = -3

 

Approved by eNotes Editorial Team

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