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Kyle is asked to solve a system of equations by substitution: 2x + 3y = 12 x - 2y = 4 which step should kyle take first? why?

a.kyle should solve the first equation for y because 12 is divisible by 3.
b.kyle should solve the second equation for y because y is being subtracted.
c.kyle should solve the second equation for x because x has a coefficient of 1.
d.kyle should solve the first equation for x because x has a coefficient greater than 1.

2 Answers

4 votes
the correct answer is C
User Paras Korat
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The given system of equations is


2x + 3y = 12 and


x - 2y = 4

From the given set of options, it would be best for Kyle if he takes option C as the first step. That is, "Kyle should solve the second equation for x because x has a coefficient of 1".

This is because it will make further solution easy. Let us know how.

The coefficient of x is 1. Thus, x will be represented as:
x=4+2y after adding
2y to both sides. Now, this can be substituted in the first equation and we can solve for y. Once that is done we can easily solve for x using any of the two equations (whichever is the easiest).

User Miroslav
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8.1k points