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.
I just tried to help someone with the same problems. I hope this helps you
1 1/4 hours. When you add them that’s what you get.
1) D
2)
3) B
4 ) F
5)C
6) F
7) D
8) C
I'm not sure about questions 4 and 7, but they may be correct.
I couldn't because I couldn't see the 2nd question
1/2
If ABC ~ DEF then 12/6, 16/8, and 18/9 would equal 2
BUT since we are going from a large triangle to a small triangle, our answer needs to be less then one, making our answer 1/2
