Answer:
18
Step-by-step explanation:
2x+y=9
3x+5y=19
I will do this problem in 2 ways. I.)Substitution II.)Elimination
Solution I.) Substitution
We can subtract 2x from both sides in the first equation.
y=9-2x
Now we can substitute the y in the second equation with 9-2x
3x+5(9-2x)=19
-7x+45=19
-7x=-26
x=26/7
y=9-2(26/7)=11/7
Solution II.)Elimination
We can multiply both side of first equation by 5 to get a 5y in both equations.
10x+5y=45
Now because both are positive 5y we just need to do simple subtraction of the 2 equation, each side respectively.
(10x+5y)-(3x+5y)=45-19
7x=26
x=26/7
2*26/7+y=9
y=11/7
Ultimately you get the same answer, both are viable methods, some problems are faster with one method but I recommend mastering both since they are very useful.
C-7 hours, 0 minutes because between 8 and 11 are 3 hours and between 12 and 4 are 4 hours. 3+4= 7 hours
Answer:
6.2y - 3.7
Step-by-step explanation:
−y+5.3+7.2y−9
Subtract 9 from 5.3 to get −3.7.
−y−3.7+7.2y
Combine −y and 7.2y to get 6.2y.
6.2y−3.7
We need the picture or is it just the question?
