Answer:
7*(1/10)= the third one
Step-by-step explanation:
If you solve for x you get:
x=(<span><span><span>5/2)</span>y</span>+<span>10
</span></span>
If you solve for y you get:
y=(<span><span><span>2/5)</span>x</span>−<span>4</span></span>
3x - y = 9
y = -2x + 11
3x - (-2x + 11) = 9
3x + 2x - 11 = 9
3x + 2x = 9 + 11
5x = 20
x = 20/5
x = 4
y = -2x + 11
y = -2(4) + 11
y = -8 + 11
y = 3
solution (where the lines intersect) is (4,3)
Area= a*height
the formula for an isosceles trapezoid is 1/2(base1+base2)*height. 1/2 base 2 and 2a will simplify to a base length of a. a times height or a*height
10)

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12)

13) (your answer is incorrect)

14) (your answer is incorrect)

15)

16)
-expression to represent this situation

Answer: In 1 group 57 students
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