I won't answer them all for you (don't want to cheat - need to learn something).
But for the first one given:
<span>-2x-9y=-25
-4x-9y=-23
you set up either x or y (which ever one you want to eliminate) so that one of them cancels.
So this one is easy - you just have to multiply an entire row by negative (doesn't matter which one) - so that the y's will be + and -
Since they're both 9 and they're subracting NOW - you can eliminate the y value. Now add/subtract the x's. So it'd be -2 or 2 depending on how you eliminated y. Then add the number outside of the = sign. Now just solve for x. After that plug in whatever you got for x into both of the rows. Then find the y value.
Hopefully this wasn't confusing -- reply if it is and I will try to simplify. I can give you contact if you need help with the rest
Good luck!</span>
Answer:
x = -3
, y = 0
Step-by-step explanation:
Solve the following system:
{4 x - y = -12 | (equation 1)
-x - y = 3 | (equation 2)
Add 1/4 × (equation 1) to equation 2:
{4 x - y = -12 | (equation 1)
0 x - (5 y)/4 = 0 | (equation 2)
Multiply equation 2 by 4/5:
{4 x - y = -12 | (equation 1)
0 x - y = 0 | (equation 2)
Multiply equation 2 by -1:
{4 x - y = -12 | (equation 1)
0 x+y = 0 | (equation 2)
Add equation 2 to equation 1:
{4 x+0 y = -12 | (equation 1)
0 x+y = 0 | (equation 2)
Divide equation 1 by 4:
{x+0 y = -3 | (equation 1)
0 x+y = 0 | (equation 2)
Collect results:
Answer: {x = -3
, y = 0
Answer: le quedan leer 295 páginas
Step-by-step explanation:
5 % of the students choose other. 95% choose either Saturday or Sunday.
Let x be the number of students who participated.
(5/100) * x = 8 Multiply both sides by 100
5 * x = 8*100
5*x = 800 Divide by 5
x = 800/5
x = 160 students participated in the survey <<<<< Answer
Prime= 19, 37, and 47
Composite= 9, 15, 26, 33, and 45
Hope this helps!
