Answer:
20 miles
Step-by-step explanation:
Set up a proportion...
0.8 miles is to x miles as 6 mins is to 2.5 hours
*You need to convert 2.5 hours into minutes first, since the first part is in minutes. There are 60 minutes in an hour, so there are 60(2.5) = 150 minutes in 2.5 hours
0.8/x = 6/150
Now solve for x by cross multiplying...
0.8(150) = 6x
120 = 6x
20 = x
She can ride 20 miles in 2.5 hours
3x - y = 9
-2x -y = -11 |* -1
3x - y = 9 } +
2x+y = 11
-------------
5x / =20
x=20:5
x=4
3x -y = 9
3*4 - y = 9
12 - y= 9
y=12-9
y=3
(4,3) is the solution
Answer:
x = 15/p
Step-by-step explanation:
4(px + 1) = 64
4px + 4 = 64
-4 -4
4px/p = 60/p
4x/4 = 60/p/4
x = 15/p
Answer:
i believe its -4 and -2
Step-by-step explanation:
hope tha work
It's a simultaneous equation:
Steps:
1.Number the equations..
a+b=77 -1
a-b=13 -2
2. Choose what variable you want to use. In this case I would use the "b". Since the signs in front of the "b's" are different, add the two equations together
a + b = 77
+ + +
a (-b) = 13
Which gives;
2a = 90
Then solve to find a:
2a=90
a= 90/2
a=45
3.Then plug the "a" value into any of the original equations to find the "b" value. I would use equation 1 since the all the variables are positive.
a + b = 77
(45) + b = 77
b=77-45
b=32
4.Solution
a=45
b=32
