What is 3(5x^2-9x) evaluated for x=-3
2 answers:
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Answer:
all real numbers.
Step-by-step explanation:
9x - 8y = 1
18x - 16y = 2
if you look at the first equation, you can figure out what y equals.
9x - 8y = 1
<em>add 8y to both sides</em>
9x = 1 + 8y
<em>subtract 1 from both sides</em>
9x - 1 = 8y
<em>divide both sides by 8</em>
= y
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now, substitute y in the second equation.
18x - 16y = 2
18x - 16() = 2
18x - 2(9x - 1) = 2
18x - 18x +2 = 2
2 = 2
the answer is <em>all real numbers, </em>because regardless of what x equals, 2 will always equal 2.