2x-y=7
2x+7y=31 |* (-1)
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2x - y = 7
-2x-7y=-31
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-y-7y=-24
-8y=-24 |:(-8)
y=3
2x-y=7
2x-3=7 |+3
2x=10 |:2
x=5
x=5
y=3
A Triangle has the same amount of points and sides, 3.
Answer:
240 cm², A = 300 cm², and 540 cm²
Step-by-step explanation:
1) The area of a parallelogram is A = bh, so:
A = (20)(12)
A = 240 cm²
2) Similarly, the area of a rectangle is A = bh, so:
A = (15)(20)
A = 300 cm²
3) The composite area is the sum of both the rectangle's area and the parallelogram's area, so:
240 cm² + A = 300 cm² = 540 cm²