
If 2x+y=5, then y=5-2x, so he substituted 5-2x correctly.
x+4x=5x, so he combined like terms correctly.
If 5x-10=10, then 5x=10+10 -> 5x=20, so he subtracted 10 from the right side instead of adding 10 to the right side.
The answer is C.
Here's the correct solution:
The unknown is how many girls and boys are in the class.
Yes it is a function because non of the X values are repeating
Answer:
1/4
Step-by-step explanation:
3 out of 12 stored over 10:
3 / 12
simplify
1/4
Answer:
3 dogs and 2 cats.
Step-by-step explanation:
In this case we can solve it using a 2x2 system of equations, like this:
let x: number of cats
let y: number of dogs
So:
42.5 * x + 64 * y = 277
35.5 * x + 50.5 * y = 222.5 => x = (222.5 - 50.5 * y) /35.5
Replacing, we are left with that:
42.5 * (222.5 - 50.5 * y) /35.5 + 64 * y = 277
266.37- 60.45 * y + 64 * y = 277
64 * y - 60.45 * y = 277 - 266.37
3.55 * y = 10.63
y = 10.63 / 3.55
y = 2.99, about 3
Now to calculate x:
x = (222.5 - 50.5 * 3) /35.5
x = 2
Which means that it has a total of 3 dogs and 2 cats.