Answer:
Option B: 3x + 3y - 3
Step-by-step explanation:
In an isosceles triangle, the two congruent sides are equal.
We are told the base is; x - y - 2 units
Now let each of the congruent sides be represented as A.
Thus the perimeter equation will be;
P = 2A + x - y - 2
Now, we are told that the perimeter is; 7x + 5y - 8 units
Thus;
7x + 5y - 8 = 2A + x - y - 2
Rearranging gives;
7x - x + 5y + y - 8 + 2 = 2A
2A = 6x + 6y - 6
Divide through by 2 to give;
A = 3x + 3y - 3 units
Number of weekend minutes used: x
Number of weekday minutes used: y
This month Nick was billed for 643 minutes:
(1) x+y=643
The charge for these minutes was $35.44
Telephone company charges $0.04 per minute for weekend calls (x)
and $0.08 per minute for calls made on weekdays (y)
(2) 0.04x+0.08y=35.44
We have a system of 2 equations and 2 unkowns:
(1) x+y=643
(2) 0.04x+0.08y=35.44
Using the method of substitution
Isolating x from the first equation:
(1) x+y-y=643-y
(3) x=643-y
Replacing x by 643-y in the second equation
(2) 0.04x+0.08y=35.44
0.04(643-y)+0.08y=35.44
25.72-0.04y+0.08y=35.44
0.04y+25.72=35.44
Solving for y:
0.04y+25.72-25.72=35.44-25.72
0.04y=9.72
Dividing both sides of the equation by 0.04:
0.04y/0.04=9.72/0.04
y=243
Replacing y by 243 in the equation (3)
(3) x=643-y
x=643-243
x=400
Answers:
The number of weekends minutes used was 400
The number of weekdays minutes used was 243
Answer:
As you can see, the curve and the line intersect at (3, 4) and (8, 9), so the two x values where they intercept are 3 and 8.
