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PLEASE HELP!!! (WORTH 50 POINTS!!!)

4y + 3x = -6
y-x=-5
how can you eliminate the x terms in this system

PLEASE HELP!!! (WORTH 50 POINTS!!!) 4y + 3x = -6 y-x=-5 how can you eliminate the-example-1
User AyB
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1 Answer

6 votes

Answer:

you can eliminate the x terms in this system by multiplying each side by 3.

Explanation:

in order to eliminate a variable from a system of equations, you must multiply whatever variable you want to eliminate (in this case, x) by a number that will make the variable you want to eliminate in the first (4y+3x=-6) and second (which is y-x= -5) equations cancel out when adding them together

a written example for further clarification:

step 1:

4y + 3x = -6

3*(y - x = -5)

up here, you can see i'm multiplying the bottom equation by 3 in order to change the value of x from x to -3x, so that when you add the top and the bottom equations together, x is nowhere to be found in the resulting equation (this is what you want)

step 2:

distribute the 3 to all terms in the second equation. this gives you:

(3y-3x = -15).

step 3:

now add this new equation to the first equation (4y+3x=-6).

This gives you:

4y+3x=-6

+

3y-3x=-15

then just add the like terms (4y and 3y, 3x and -3x, -6 and -15).

which gives you (7y=-21)

see how x is not in the resulting equation? you have now successfully eliminated it :] hope this helped!

User Zizther
by
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