You want to eliminate one of the terms (x or y) in one of the equations so you can solve for the other variable. You have to multiply by the opposite number of the coefficient to be able to eliminate the term in the other equation. If the x coefficient is 2, then you have to multiply the entire other equation by -2. If the y coefficient is -5, then you have to multiply the entire other equation by 5.
10)
-4x + 9y= 9
x - 3y= -6
STEP 1:
multiply the bottom equation by 4
4(x- 3y)= 4(-6)
4x - 12y= -24
STEP 2:
add the top equation and the equation from step 2
-4x + 9y= 9
4x - 12y= -24
the x term cancels out
-3y= 15
divide both sides by -3
y= -5
STEP 2:
substitute the y value in either original equation to solve for x
x - 3y= -6
x - 3(-5)= -6
x + 15= -6
subtract 15 from both sides
x= -21
ANSWER: x= -21; y= -5
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12)
-7x + y= -19
-2x + 3y= -19
STEP 1:
multiply the top equation by -3 to eliminate the y term and to solve for x
-3(-7x + y)= -3(-19)
21x - 3y= 57
STEP 2:
add the bottom equation and the equation from step 2 to solve for x
-2x + 3y= -19
21x - 3y= 57
the y term cancels out
19x= 38
divide both sides by 19
x= 2
STEP 3:
substitute the x value in step 2 to solve for y; you can use either original equation
-7x + y= -19
-7(2) + y= -19
-14 + y= -19
add 14 to both sides
y= -5
ANSWER: x= 2; y=-5
Hope this helps! :)
Answer:
See below in bold.
Step-by-step explanation:
As we see from the diagram the x -intercept ( where the line intercepts the horizontal x-axis) is (3, 0) and the y-intercept is (0, -10).
15 electricians worked for 24 days to the whole job, now, there are 15 of them, so on any given day, each electrician worked one whole day, in 24 days, that one electrician worked 24 days total.
now, there were 15 electricians on any given day though, since each one of them worked the whole day that one day, so the "days work worth" on a day is 15, so the house gets 15days worth of work because of that.
so how many "days worth" did all 15 do on the 24 days, well, 15+15+15+15+15+15+15+15+15+15+15+15+15+15+15+15+15+15+15+15+15+15+15+15, namely 15 * 24, or 360 days worth of work.
since it takes 360 days worth of work to do the whole wiring, in how many days would 18 electricians do it? 360/18.
1.5y < -6.75
First, divide both sides by '1.5'.
Second, since 4.5 × 1.5 = 6.5, simplify the fraction to '-4.5'
Answer:
y < -4.5
Answer:
5
Step-by-step explanation:
(-3)(2)-7(-3)-10
-6+21-10
15-10
5
