Answer: " x = 1 ".
The answer for this 'system of equations' is: " [1, 15] ".
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Explanation:
To solve for x :
Given:
y = 3x + 18
y = 15 ;
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We know that:
3x + 18 = 15 ; Now, subtract 18 from Each Side of the equation:
3x + 18 − 18 = 15 − 18 ;
to get:
3x = 3 ; Now, divide Each Side of the equation by 3 ;
to isolate x on one side of the equation;
and to solve for x :
3x / 3 = 3 / 3 ;
to get: x = 1
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The answer is: " x = 1 " ;
The answer for this 'system of equations' is:
" [1, 15] " <== { written as: " [x, y] "} ;
in which: " y = 15 " ; is given in the problem.
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Hope this answer is helpful.
Best wishes!
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