Answer:
b. (1, 3, -2)
Step-by-step explanation:
A graphing calculator or scientific calculator can solve this system of equations for you, or you can use any of the usual methods: elimination, substitution, matrix methods, Cramer's rule.
It can also work well to try the offered choices in the given equations. Sometimes, it can work best to choose an equation other than the first one for this. The last equation here seems a good one for eliminating bad answers:
a: -1 -5(1) +2(-4) = -14 ≠ -18
b: 1 -5(3) +2(-2) = -18 . . . . potential choice
c: 3 -5(8) +2(1) = -35 ≠ -18
d: 2 -5(-3) +2(0) = 17 ≠ -18
This shows choice B as the only viable option. Further checking can be done to make sure that solution works in the other equations:
2(1) +(3) -3(-2) = 11 . . . . choice B works in equation 1
-(1) +2(3) +4(-2) = -3 . . . choice B works in equation 2
QUESTION A
The given points are
and 
The slope can be found using the formula;
We substitute the point to obtain;
This simplifies to
Therefore the slope is 5.
QUESTION 2
A positive slope indicates a rising line
A negative slope indicates a rising line
A zero slope means the line is horizontal.
An undefined slope means the line is vertical.
The correct answer is
A. The line rises from left to right.
To solve a system of linear equations graphically we graph both equations in the same coordinate system. The solution to the system will be in the point where the two lines intersect. The two lines intersect in (-3, -4) which is the solution to this system of equations
Answer:
2. Alex sent the questionnaire only to those who live near her.
Step-by-step explanation:
Given scenario is :
Alex is conducting a survey for a car company. She decides to start by interviewing some people in her neighborhood.
She prepares a questionnaire and emails it to 50 neighbors who own cars. Of those neighbors, 24 respond.
We can see that Alex sent the questionnaire to only her neighbors or people who live near her, so this will be the reason the sample will be biased.
