Answer:
x=28
Step-by-step explanation:
vertical angles are congruent
3x-12=72
3x=84
x=28
Answer:
16
General Formulas and Concepts:
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
Equality Properties
- Multiplication Property of Equality
- Division Property of Equality
- Addition Property of Equality
- Subtraction Property of Equality<u>
</u>
<u>Trigonometry</u>
[Right Triangles Only] Pythagorean Theorem: a² + b² = c²
- a is a leg
- b is another leg
- c is the hypotenuse<u>
</u>
Step-by-step explanation:
<u>Step 1: Define</u>
<em>Identify variables</em>
Leg <em>a</em> = <em>a</em>
Leg <em>b</em> = 12
Hypotenuse <em>c</em> = 20
<u>Step 2: Solve for </u><em><u>a</u></em>
- Substitute in variables [Pythagorean Theorem]: a² + 12² = 20²
- Evaluate exponents: a² + 144 = 400
- [Subtraction Property of Equality] Isolate <em>a</em> term: a² = 256
- [Equality Property] Square root both sides: a = 16
This does not appear to be a right triangle. However, we know 2 sides and the included angle, so can find the unknown side length. Let x represent this length. Then:
x^2 = (9 m)^2 + (12 m)^2 - 2(9m)(12 m)*cos 30 degrees, or
x^2 = 81 + 144 - 216(sqrt(3) / 2). Please solve for x^2 and then solve the result for x, making sure to choose the positive value. The result will be the length of the side opposite the 30 degree angle.
With 1 of 3 angles known, and 3 of 3 sides known, you can use the Law of Sines to find the other two angles. As a reminder, the Law of Sines looks like this:
a b c
-------- = --------- = ----------
sin A sin B sin C.
You can give the 30-deg angle any name you want; then a, the length of the side opposite the 30-deg angle, which you have just found. And so on.
Every day she spends 35 euros
she had 315+35=350 euros
The answer world be D 8 pounds