Answer:
(f + g)(x) = 12x² + 16x + 9 ⇒ 3rd answer
Step-by-step explanation:
* Lets explain how to solve the problem
- We can add and subtract two function by adding and subtracting their
like terms
Ex: If f(x) = 2x + 3 and g(x) = 5 - 7x, then
(f + g)(x) = 2x + 3 + 5 - 7x = 8 - 5x
(f - g)(x) = 2x + 3 - (5 - 7x) = 2x + 3 - 5 + 7x = 9x - 2
* Lets solve the problem
∵ f(x) = 12x² + 7x + 2
∵ g(x) = 9x + 7
- To find (f + g)(x) add their like terms
∴ (f + g)(x) = (12x² + 7x + 2) + (9x + 7)
∵ 7x and 9x are like terms
∵ 2 and 7 are like terms
∴ (f + g)(x) = 12x² + (7x + 9x) + (2 + 7)
∴ (f + g)(x) = 12x² + 16x + 9
* (f + g)(x) = 12x² + 16x + 9
132, if you add four to 50, and keep going until you get to 20
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:
The number of pages in each book varied more last summer than this summer
Step-by-step explanation: