Eliminate x's
multiply 2nd equation by -2 ad add to first
2x+3y=9
<u>-2x-10y=-16 +</u>
0x-7y=-7
-7y=-7
divide by -7
y=1
sub back
2x+3y=9
2x+3(1)=9
2x+3=9
minus 3
2x=6
divide 2
x=3
x=3
y=1
(x,y)
(3,1)
D
Hi,
81 is 37.5% of 216.
"1. We assume, that the number 37.5 is 100% - because it's the output value of the task.
2. We assume, that x is the value we are looking for.
3. If 100% equals 37.5, so we can write it down as 100%=37.5.
4. We know, that x% equals 81 of the output value, so we can write it down as x%=81.
5. Now we have two simple equations:
1) 100%=37.5
2) x%=81
where left sides of both of them have the same units, and both right sides have the same units, so we can do something like that:
100%/x%=37.5/81
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.
7. Solution for 81 is what percent of 37.5
100%/x%=37.5/81
(100/x)*x=(37.5/81)*x - we multiply both sides of the equation by x
100=0.46296296296296*x - we divide both sides of the equation by (0.46296296296296) to get x
100/0.46296296296296=x
216=x
x=216 "
Have a great day!
The known endpoint is P = (-16,0)
Let Q = (x,y) be the other endpoint. It is unknown for now.
Looking at the x coordinates of P and Q, we see that they are -16 and x respectively. Adding these values up gives -16+x. Dividing that result by 2 gives (-16+x)/2. This result is exactly equal to the midpoint x coordinate, which is the x coordinate of M (0).
So we have this equation (-16+x)/2 = 0. Let's solve for x
(-16+x)/2 = 0
2*(-16+x)/2 = 2*0
-16+x = 0
x-16 = 0
x-16+16 = 0+16
x = 16
Therefore the x coordinate of point Q is 16.
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Let's do something similar for the y coordinates.
The y coordinates of P and Q are 0 and y respectively. Add them up and divided by 2, then set the result equal to -16 (y coordinate of midpoint M) getting this equation (0+y)/2 = -16
Solve for y
(0+y)/2 = -16
y/2 = -16
2*y/2 = 2*(-16)
y = -32
The y coordinate of point Q is -32
------------------------------------
The point Q goes from (x,y) to (16, -32)
Final Answer: (16, -32)
The correct answer is 37.5.
