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.
Answer:
80%
Step-by-step explanation:
50 x 50 would be 100 and 50kg=100% and 10 x 2 = 20 so you used 20% therefore you have 80% left.
20 and 28 can be divided by 4, so just take the 4 out so the answer should be 4(5x - 7)
Https://us-static.z-dn.net/files/d1e/04b1f4bb9da77e9bfea077c2aeee7a27.jpg
Answer:
Step-by-step explanation:
If it have more than 2 divider its composite but its divider is only one and its self only its prime.1 isn't neither prime nor composite