Respuesta :

Answer:

m=2, n=-1 or (2,-1)

Step-by-step explanation:

Hi there!

We're given this system of equations:

3n+5m=7

m-4n=6

we want to solve by substitution; in one equation, we'll set one variable to equal an expression containing the other variable, substitute that expression as the variable into the other equation, solve for the variable substituted, and use the value of that variable to find the other variable

First, let's get the expression we'll substitute into the other

let's use m-4n=6 as it has 1m (m by itself)

add 4n to both sides

m=4n+6

now substitute 4n+6 as m into 3n+5m=7 to solve for n

3n+5(4n+6)=7

do the distributive property

3n+20n+30=7

combine like terms

23n+30=7

subtract 30 from both sides

23n=-23

divide both sides by 23

n=-1

we found the value of n

now let's substitute -1 as n in m=4n+6 to find the value of m

m=4(-1)+6

multiply

m=-4+6

add

m=2

so the answer is m=2, n=-1. As a point, it's (2,-1)

Hope this helps! :)

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