Answer:
{x,y} = {25/9,23/9}
Step-by-step explanation:
// Solve equation [2] for the variable x
[2] x = -4y + 13
// Plug this in for variable x in equation [1]
[1] 5•(-4y+13) + 2y = 19
[1] - 18y = -46
// Solve equation [1] for the variable y
[1] 18y = 46
[1] y = 23/9
// By now we know this much :
x = -4y+13
y = 23/9
// Use the y value to solve for x
6 minutes/60minutes = 0.1 hrs
45miles/0.1hour = 450 miles per hour or mph
To get the solution we are looking for we need to point out what we know.
1. We assume that 55 is 100% because its the output value of the task.
2. We assume that the x is the value we are looking for.
3. If 100% = 55 so we can write it down as 100%=55
4. We know that x% = 44 of the output value so we can write it as x%=44.
5. Now we have two simple equations: 1) 100%=55 2) x%=44 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%=55/44.
6. Now we just have to solve the simple equation and we will get the answer.
7. Solution for 44 is what percent of 55 100%/x%=55/44 (100/x)*x=(55/44)*x we multiply both sides of the equation by x 100= 1.25*x we divide both sides of the equation by (1.25) to get x 100/1.25=x 80=x now we have: 44 is 80% of 55!
Quick answer = 44 is 80% of 55
Hope this helps! ;D
Answer:
16 problems.
Step-by-step explanation:
100% divided by 20 questions.
100/20 is equal to 5, therefore each question is worth 5 points.
Grade of 80% divided by points per question.
80/5 is 16 so the student answered 16 questions correctly.
