Alright, lets get started.
Justin is asked to solve the linear equations using elimination method.
By using elimination method means we have to multiply some numbers in our given equations in such a way that the co-efficient of x or y become same in both equations so that we could add or subtract them to cancel one of the term either x or y.
So, given equations are :


See we have 5x in first equation and -20x in second equation.
So, we try to change 5x into 20 x by multiplying it with 4, both of the equations will have 20 x in common
Lets multiply 4 in first equation


Now both equations could be added and 20 x will be cancelled out and we could easily find the value of y then solve for x.
So, Justin should try to change 5 so that it will be cancels, so option B : Answer
Hope it will help :)
Answer:

Step-by-step explanation:
y=x^2-x+1
We want to solve for x.
I'm going to use completing the square.
Subtract 1 on both sides:
y-1=x^2-x
Add (-1/2)^2 on both sides:
y-1+(-1/2)^2=x^2-x+(-1/2)^2
This allows me to write the right hand side as a square.
y-1+1/4=(x-1/2)^2
y-3/4=(x-1/2)^2
Now remember we are solving for x so now we square root both sides:

The problem said the domain was 1/2 to infinity and the range was 3/4 to infinity.
This is only the right side of the parabola because of the domain restriction. We want x-1/2 to be positive.
That is we want:

Add 1/2 on both sides:

The last step is to switch x and y:



Answer:
the constant proportionality means the ratio between two directly proportional quantities.
so the constant proportionality will be 7.5÷6=1.25 or 10÷8=1.25 or 12.5÷10=1.25
constant proportionality should be same all through because it's a constant
Answer:
C
Step-by-step explanation:
Translate the image 2 units right and 1 unit up. Then rotate the image 180°.
Take the coordinate W, it is at (2, 4).
Translate 2 units right (add 2 to the x coordinate) and 1 up (add 1 to the y coordinate)
(2, 4) ------> (2 + 2, 4 + 1) -------> (4, 5)
A rotation of 180° (doesn't matter the direction) makes the coordinates their opposites. Positives become negatives and negatives become positive.
(4, 5) -------> (-4, -5)