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4 votes
Solve the system using substitution.
5x+ 4y = 10
4x - y = 8

User Saarrrr
by
3.2k points

2 Answers

3 votes

Answer: x = 2, y = 0 or (2 , 0)

Explanation:

Solving using substitution is where you solve for a variable in one of the two equations in the system then plug it into the other.

For an easier plug in we can take the second equation. 4x-y = 8.

From here we need to isolate the y variable which is easier to isolate than x, in my opinion.

Subtract the 4x over.

-y = 8-4x

Now divide by a -1 so y is positive.

y= -8 + 4x

Now plug this in for y in the other equation.

5x + 4(-8 + 4x) = 10

Distribute the 4.

5x - 32 + 16x = 10

Combine like terms

21x - 32 = 10

Add the 32.

21x = 42

Divide by 21.

x = 2

Now that we have solved for one variable we can plug this into either equation and solve for the other.

I will plug it into the second equation.

4(2) - y = 8

Simplify.

8 - y = 8

Subtract 8.

-y = 0

Divide by -1.

y = 0

So the x and y values are.

x = 2

y = 0

User Electric Monk
by
3.6k points
7 votes

Answer:

Explanation:

hello

from 4x-y=8 we can say that y = 4x-8

we substitute in the first equation to get

5x + 4 (4x-8) = 10

then

5x + 16 x -32 = 10

<=> 21x = 32+10=42

<=> x = 42/21 = 2

and then y = 8-8=0

don t hesitate if you need any further explanation

thanks

User Ferr
by
3.9k points