Answer:
9) 3rd side = 2x+2y
10) 5a^2 + 6a - 3
Step-by-step explanation:
9) 10x+5y - ( 3x+ 4y) = 7x + y
7x + y - ( 5x - y ) = 2x + 2y
10)
Answer:
85, 68, 51
Step-by-step explanation:
Average: The sum of all the numbers divided by the number of numbers
If the ratio of the scores is 5 : 4 : 3, let's just set it as 5x : 4x : 3x
Then using the definition of an average, we can write this equation.
(5x + 4x + 3x) / 3 = 68
Multiply both sides by 3.
5x + 4x + 3x = 68 * 3
Simplify.
12x = 204
x = 17
Now, substitute x = 17 into the original scores (5x, 4x, and 3x)
5x = 5 * 17 = 85
4x = 4 * 17 = 68
3x = 3 * 17 = 51
Just in case, let's check this answer. Find the average of the 3 test scores.
(85 + 68 + 51) / 3 =
204 / 3 = 68
Thus, the answers are correct
The equation 
has 2 and x in common. This means you can factor both the 2 and x out of the equation like so...
2x(
)
Hope this helped!
~Just a girl in love with Shawn Mendes
At least 21....I hope you pass what ever you are doing!
Answer: 80 minutes
Step-by-step explanation:in the picture
