I believe you are expected to simplify. To do this all you do is group like terms (x, x², x³ etc.) and then simplify the coefficients.
13. 10z + 7z - 19z² - 5z² - 17z
first you can rearrange and group like terms (remember the bring the sign in front of each term with it). I would do it like this:
-19z² - 5z² +10z + 7z - 17z
Now simplify the coefficients:
-24z² + 0z
you can omit the 0z and your simplified answer is
-24z²
Main thing to remember here is that z and z² cannot be simplified together, nor can any variable that has an exponent because the exponent makes them differ.
(x-5) = 0 or (x+2)=0
so x could be 5 or -2
i guess, u can check it with calculator
ANSWER
The approximate solution is

EXPLANATION
The point of intersection of the two lines is the solution of the linear systems represented by the graph.
From the graph we can determine that each box is 2 units.
From the graph, when we start at O and count two boxes to the right and half box down, we obtain the point of intersection of the two lines to be

Note that since each box is two units, half way between the boxes gives one unit.
Answer:

Step-by-step explanation:
The equation of a line is usually written in the form of y=mx+c, where m is the gradient and c is the y-intercept.
The product of the gradients of perpendicular lines is -1.
Gradient of given line= 3.
(Gradient of line)(3)= -1
3m= -1
m= 
subst. m=
into the equation:

To find the value of c, substitute a coordinate.
When x=0, y=4,

Thus the equation of the line is
.
<span>2+1/6y=3x+4 solve for y
</span>
Answer y=18x+12