Answer:
What is missing is -5x - 20
Step-by-step explanation:
To find this, simply solve for the parenthesis as if it were a variable of its own. This will allow you to see exactly what is missing.
8x - (x - 20) = 2x - (_______)
8x - x + 20 = 2x - (_______)
7x + 20 = 2x - (_______)
5x + 20 = - (_______)
-5x - 20 = (_______)
So the answer for the parenthesis is -5x - 20
direct proportion y=kx , k is constant and k does not equal to 0.
17.5=k(21)
k=5/6
when x =39
y=5/6 ×39
y=32.5
Answer:
AC = 52
Step-by-step explanation:
Add the segment lengths together.
AB + BC = AC
22 + 30 = 52
Substitute the first equation into the second equation. You will get:
4x - (2x - 5) = 7
Distribute the negative sign into the parenthesis:
4x - 2x + 5 = 7
Simplify
2x + 5 = 7
Subtract 5 on both sides
2x = 2
x = 1
Now, substitute x = 1 into the first equation:
y = 2(1) - 5
y = 2 - 5
y = -3
The solution to the system of equations is (1, -3).
Hints on solving trigonometry problems:
If no diagram is given, draw one yourself.
Mark the right angles in the diagram.
Show the sizes of the other angles and the lengths of any lines that are known
Mark the angles or sides you have to calculate.
Consider whether you need to create right triangles by drawing extra lines. For example, divide an isosceles triangle into two congruent right triangles.
Decide whether you will need Pythagorean theorem, sine, cosine or tangent.
Check that your answer is reasonable. The hypotenuse is the longest side in a right triangle.
How to use the tangent ratio to find missing sides or angles?
Example:
