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CEMC Cayley, 2020

Algebra Difficulty 1.1 Junior Find the answer Canada

When $x=3$ and $y=4$ , the value of $xy-x$ is

$3$
$4$
$12$
$9$
$15$

Your answer

A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.

Solution

When $x=3$ and $y=4$ , we get $xy - x = 3 \times 4 - 3 = 12 - 3 = 9$ .

Alternatively, $xy - x = x(y-1) = 3 \times 3 = 9$ .

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