Let n = cost of 1 notebook
Let p = cost of 1 pencil
Then,
3n + 4p = 8.5
5n + 8p = 14.5
You can solve for one variable in terms of the other and then substitute into the remaining equation.
3n + 4p = 8.5
+ 5n + 8p = 14.5
Multiply the top equation by -2 so that the p-containing terms cancel each other out:
-2(3n + 4p = 8.5)
+ 5n + 8p = 14.5
-n + 0 = -2.5
So after dividing both sides by -1, we see that n = $2.5. Plugging into the first equation gives p = $0.25.
3n + 4p = 8.5
5n + 8p = 14.5
Answer: D 120%
Step-by-step explanation:
The value of the function at x = -1 is 5
<h3>What is function?</h3>
Function can be defined as an expression, rule, or law that defines a relationship between one variable known as the independent variable and another called the dependent variable.
From the information given, we have that;
f (x) = 3 (2)x with x=-1
Now, let's substitute the value of x as - 1 in the function given;
f (x) = 3 (2)x
f (x) = 3 (2) -1
Expand the bracket;
f (x) = 6 - 1
f(x) = 5
Thus, the value of the function at x = -1 is 5
Learn more about functions here:
brainly.com/question/6561461
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Problem: 2/7 (4+c)=6
1. 7/2 x 2/7 x (4+c)=7/2 x 6
2. 4+c=7 x 3
3. 4+c=21
4. c=21-4
Answer: c=17
