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Algebra Difficulty 1.9 Junior Find the answer

If x=11x=11, y=−8y=-8, and 2x−3z=5y2x-3z=5y, what is the value of zz?

A number or a short expression. Spacing and $ signs are ignored.

Solutions — 2

Solution 1

Since x=11x=11, y=−8y=-8 and 2x−3z=5y2x-3z=5y, then 2×11−3z=5×(−8)2 \times 11-3z=5 \times(-8) or 22−3z=−4022-3z=-40. Therefore, 3z=22+40=623z=22+40=62 and so z=623z=\frac{62}{3}.

Solution 2

Since x=11,y=8x=11, y=8 and 2x+3z=5y2x+3z=5y, then 2×11+3z=5×82 \times 11+3z=5 \times 8 or 3z=40−223z=40-22. Therefore, 3z=183z=18 and so z=6z=6.

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