Answer:
D. Subtract 4 from both sides
Explanation:
I just learned about quadratic equations in school. The first step of solving quadratic equations is to make sure it is in standard form and equal to 0.
Standard form:
ax^2 + bx + c = 0
3r+1w=5
5r+1w=80
System of equations :)
Answer:
There is no short answer.
Step-by-step explanation:
To find to intervals which f(x) increases or decreases, we first need to find it's derivative.

The function is increasing when it's value is > 0 and decreasing when it's value is < 0.
If we take a look at this graph, cosx+sinx is positive when they are both positive or when cosx is greater then sinx on the negative part.
I hope this answer helps.
4 / 0.80 = 12 / x...cross multiply
4x = 0.80 * 12
4x = 9.6
x = 9.6 / 4
x = 2.4.....12 apples cost $ 2.40