Part 1 :
if the number of hours (h) is greater than 7.
Equation for the amount(A) in dollar is
Amount (A) = 210 + (h-7)x20
Part 2 :
if she earns 410,
with the same equation
410 = 210 + (h-7)x 20
200 =(h-7)x 20
10 = h-7
17 = h
therefore, number of hours tutored is 17.
Step-by-step explanation:
(1 + cos θ + sin θ) / (1 + cos θ − sin θ)
Multiply by the reciprocal:
(1 + cos θ + sin θ) / (1 + cos θ − sin θ) × (1 + cos θ + sin θ) / (1 + cos θ + sin θ)
(1 + cos θ + sin θ)² / [ (1 + cos θ − sin θ) (1 + cos θ + sin θ) ]
(1 + cos θ + sin θ)² / [ (1 + cos θ)² − sin² θ) ]
Distribute and simplify:
(1 + cos θ + sin θ)² / (1 + 2 cos θ + cos² θ − sin² θ)
[ 1 + 2 (cos θ + sin θ) + (cos θ + sin θ)² ] / (1 + 2 cos θ + cos² θ − sin² θ)
(1 + 2 cos θ + 2 sin θ + cos² θ + 2 sin θ cos θ + sin² θ) / (1 + 2 cos θ + cos² θ − sin² θ)
Use Pythagorean identity:
(2 + 2 cos θ + 2 sin θ + 2 sin θ cos θ) / (sin² θ + cos² θ + 2 cos θ + cos² θ − sin² θ)
(2 + 2 cos θ + 2 sin θ + 2 sin θ cos θ) / (2 cos² θ + 2 cos θ)
(1 + cos θ + sin θ + sin θ cos θ) / (cos² θ + cos θ)
Factor:
(1 + cos θ + sin θ (1 + cos θ)) / (cos θ (1 + cos θ))
(1 + cos θ)(1 + sin θ) / (cos θ (1 + cos θ))
(1 + sin θ) / cos θ
Before you use the quadratic formula, you have to make sure the equation itself is a quadratic and that a and b are not 0.
Answer:
70
Step-by-step explanation:
Substitute x with -6:
2(-6)²-2
2(36)-2
72-2
70
Using a system of equations, it is found that Gina got 22 questions correct in the test.
<h3>What is a system of equations?</h3>
A system of equations is when two or more variables are related, and equations are built to find the values of each variable.
In this problem, the variables are:
- Variable x: Number of questions she got correct.
- Variable y: Number of questions she got wrong.
The test has 30 questions, hence:
x + y = 30 -> y = 30 - x.
She scored 152 points, hence, considering the value of each question:
8x - 3y = 152.
Since y = 30 - x:
8x - 3(30 - x) = 152
11x = 242
x = 242/11
x = 22
Gina got 22 questions correct in the test.
More can be learned about a system of equations at brainly.com/question/24342899
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