Question

What is the best first step for solving the given system using substitution while avoiding fractions -9x+4y=10 -9x+3y=3

Answer 1

Solve for x in the second equation.

Explanation:

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Answer 2

The best first step for solving the given system using substitution is substitute the value of -9x from equation 1 in equation 2

Explanation:

Given :
`-9x+4y=10`

`-9x+3y=3`

To Find: What is the best first step for solving the given system using substitution?

Solution:

`-9x+4y=10` --1

`-9x+3y=3` --2

Since we are supposed to solve these equations using substitution method

So, the first best step for solving the equation is :

Both the equations contains -9x

So, substitute the value of -9x from equation 1 in equation 2

`10-4y+3y=3`

`10-y=3`

`y=7`

Substitute the value of y in 1 to get value of x

So,
`-9x+4(7)=10`

`-9x+28=10`

`9x=18`

`x=2`

Thus the solution is (2,7)

Hence the best first step for solving the given system using substitution is substitute the value of -9x from equation 1 in equation 2