Question

solve the system using substation. Enter answer in ordered pair form (a,b)
a+b=4
2a+3b=11

Answer 1

First isolate b in a+b=4 to get...

a+b=4

a+b-a=4-a

b = 4-a

Answer 2

Then plug this into 2a+3b=11 to get

2a+3b=11

2a+3(4-a)=11 ... replace b with 4-a

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solve for 'a' in the equation 2a+3(4-a)=11 gives you a = ???

Answer 3

what do you get when you distribute 3(4-a)

Answer 4

12-3

Answer 5

12-3a actually

Answer 6

2a+3(4-a)=11

2a+12-3a=11

-a+12 = 11

a = ???

Answer 7

id subtract12 from 11 correct?

Answer 8

correct

Answer 9

minus 12 on both sides so you get an equation that looks like -a = -1

Answer 10

-a = 11 - 12

-a = -1

a = 1

Answer 11

Once you know a = 1, use it to find that

b = 4-a

b = 4-1

b = 3

Answer 12

oh okay o get it.