If we substitute equation (2) into (1) then we have the equivalent equations; y = 5 - x and 5 - x = 9x².
<h3>What is a mathematical equation?</h3>
An equation must contain two sets of variables, the independent variable and the dependent variable separated by the equality sign.
In this case, the original system of equations are; y = 9x² and x + y = 5. It the follows that, if we substitute equation (2) into (1) then we have the equivalent equations; y = 5 - x and 5 - x = 9x².
<span>The place value positions to either side of a number are related because they are 10 times smaller or ten times bigger — a number in the hundreds column in ten times bigger than the same number in the tens column, for example.</span>
the communitive property states that if: a+b=c, then b+a=c
if each ballon costs 2 dollars, that would b 2x or $2 (aka the 2) for 1 balloon (aka the x) and since he has a 10$ off coupon, you have to subtract 10$ so y=2x-10