Answer for problem 1: slope = 2, y intercept = 3
Answer for problem 2: slope = 3/4, y intercept = -2
Explanation:
Both equations are in the form y = mx+b. This is known as slope intercept form. This is because we can read off the values of the slope and y intercept very quickly. We have y = 2x+3 match up with y = mx+b. The m is the slope and b is the y intercept. So m = 2 and b = 3 for this equation. A similar situation happens with the other equation as well. It might help to rewrite the second equation into y = (3/4)x + (-2).
See if the distance between the two lines is consistent with a compass.
Make sure the lines intersect at right angles with the corner of a piece of paper.
Measure each of the angles with a straightedge.
There is no way to ensure you have constructed parallel lines.
Okay so to represent juice we are going to use X, and to represent water we are going to use Y.
We also know that the first two starting equations are:
6x + y = 135
4x + 2y = 110
We can re-arrange the first equation so that it equals y (for now), so it is going to end up looking like this:
y = -6x +135
Now you can take that equation and plug into either one of the starting two equations. I chose the second equation. We just substitute what y equals in for y in the equation, so we have:
4x + 2(135 - 6x) = 110
Now solve
4x + 270 -12x = 110
-8x + 270 = 110
Subtract 270 from both sides
-8x = -160
Now divide by -8 on both sides
x = 20
We can now confirm that juice costs $20
Now lets plug that into the equation where we solved for y, to get the actual value of y.
y = 135 - 6(20)
y = 135 - 120
y = 15
The price of water costs $15
From this we can conclude that the cost of juice is $20 and the price of water is $15
The given expression is :
2xx+3-5(x-2)
We know that, 

Aleena expands 2xx+3-5(x-2) as 2x²+3-5x-10. She is mistaken because the sign before 10 should be +10 instead of -10. Hence, the correct expanded form is 2x²+3-5x+10. Hence, this is the required solution.
You can add, subtract, and multiply them. These three operations obey the rules for integers. There's a polynomial division algorithm that fills formally the same role as the usual division algorithm for integers. Polynomials added to, subtracted from, or multiplied by other polynomials yield only polynomials. Likewise, integers added to, subtracted from, or multiplied by other integers yield only integers.