Answer:
The system of equations has a one unique solution
Step-by-step explanation:
To quickly determine the number of solutions of a linear system of equations, we need to express each of the equations in slope-intercept form, so we can compare their slopes, and decide:
1) if they intersect at a unique point (when the slopes are different) thus giving a one solution, or
2) if the slopes have the exact same value giving parallel lines (with no intersections, and the y-intercept is different so there is no solution), or
3) if there is an infinite number of solutions (both lines are exactly the same, that is same slope and same y-intercept)
So we write them in slope -intercept form:
First equation:
second equation:
So we see that their slopes are different (for the first one slope = -6, and for the second one slope= -3/2) and then the lines must intercept in a one unique point. Therefore the system of equations has a one unique solution.
No, because simplified, 20/28 would be 5/7, not 3/4
21/28 would be equivalent to 3/4 though
(5 + 7x + 6)/2 = 3x + 9
7x + 11 = 6x + 18
7x - 6x = 7
x = 7
EF = 3x + 9
= 3(7) + 9
= 21 + 9
= 30
D. 33 cm
P=2L+2W
P= 2(33)+2(40)=150