<h3>Answer: A. 5/12, 25/12</h3>
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Work Shown:
12*sin(2pi/5*x)+10 = 16
12*sin(2pi/5*x) = 16-10
12*sin(2pi/5*x) = 6
sin(2pi/5*x) = 6/12
sin(2pi/5*x) = 0.5
2pi/5*x = arcsin(0.5)
2pi/5*x = pi/6+2pi*n or 2pi/5*x = 5pi/6+2pi*n
2/5*x = 1/6+2*n or 2/5*x = 5/6+2*n
x = (5/2)*(1/6+2*n) or x = (5/2)*(5/6+2*n)
x = 5/12+5n or x = 25/12+5n
these equations form the set of all solutions. The n is any integer.
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The two smallest positive solutions occur when n = 0, so,
x = 5/12+5n or x = 25/12+5n
x = 5/12+5*0 or x = 25/12+5*0
x = 5/12 or x = 25/12
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Plugging either x value into the expression 12*sin(2pi/5*x)+10 should yield 16, which would confirm the two answers.
5x+y=-3 is the standard form
When a straight line is given the form:

m is the gradient. It shows how the value of y changes for an increase of x by 1.
So, in this case, the gradient is
4
If we intersect the circle of radius 1 around (4,-4) and the circle of radius 1 around (4,-6) they'll intersect at the center of circle radius 1 that has both those points.
Here we don't really have to do any math. It's clear that the midpoint (4,-5) is 1 away from both (4,-4) and (4,-6) so that's our answer:
Answer: (4,-5)
She saved up a total of $82.60, and had to spend a total of $60.90, so she would have $21.70 left and need to save up another $180.40, hope this helps