Solve the system of equations using elimination.

15q – 4r = 62
5q + 8r = 86
a. q = –7, r = –6
b. q = 6, r = 7
c. q = –7, r = –7
d. q = 6, r = 6

q= 6

r= 7

Step-by-step explanation:

Multiply 1st column by -2:

-30q+8r=-124

5q+8r=86

Subtract 2nd column from the first column:

-35q= -210

Solve for q:

q=6

Subtract q=6 by any of the two equations, so:

-30q+8r=-124

-30*6+8r=-124

Solve for r:

r=7

a) one student is chosen from classroom a, then a student is chosen from classroom b.  

step-by-step explanation:

independent events are ones in which the probability of one event does not affect the probability of the second event.

one student is chosen from classroom a; this does not affect the chances of choosing a student from classroom b.   this makes these independent events.

when one card is chosen from a standard deck and then set aside before a second card is chosen, the probability of the second card being chosen changes.   this makes them dependent events.

when one student is chosen from classroom a and then a second student is chosen from classroom a, the probability of choosing the second student changes.   this makes them dependent events.

when a letter is chosen from the alphabet and then a second letter is chosen, the probability of choosing the second letter changes.   this makes them dependent events.

the graph in the attached figure

step-by-step explanation:

we have

using a graphing tool

the graph in the attached figure

the roots are ( x-intercepts) x=-0.5,x=1,x=3

the y-intercept is the point (0,3)