The expression of 25t +45m shows the total number of miles driven at both speeds. In order to solve this equation you would need to know the total number of hours driven in order to multiply that by the appropriate speed in terms of miles per hour.
Answer is 82
substitute z for 9
9^2 = 81+ 1= 82
If you want to round 49.39 to the nearest tenths place you will have to look at your tenths digit.
The digit is 3, right?
Look at the next number after 3. It is the number 9 for the hundredths place. If the number is bigger than 5 you round it. If it is smaller, you keep it the same. 9 is bigger than 5 so you make the 3 into a 4.
Then, you're answer is 49.4 or 49.40 (Which are basically the same answer)
It also works the same with the other digits. Simple, right? :)
Answer:
2y = 3x + 21
y = 1.5x + 10.5
plug in, in the second equation
- 4x + (1.5x + 10.5) = 23
-4x + 1.5x + 10.5 = 23
-2.5x + 10.5 = 23
-2.5x = 12.5
x = 12.5/-2.5 = -5
y = 1.5 (-5) + 10.5 = 3
x = -5
y = 3
