8._ 7+x+66=90
x=90-73
x=17
The answer is C because it’s an acute angle
Answer:
(-3, 1)
General Formulas and Concepts:
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
Equality Properties
<u>Algebra I</u>
- Solving systems of equations by substitution/elimination
Step-by-step explanation:
<u>Step 1: Define Systems</u>
x = 2y - 5
-2x + 5y = 11
<u>Step 2: Solve for </u><em><u>y</u></em>
<em>Substitution</em>
- Substitute in <em>x</em>: -2(2y - 5) + 5y = 11
- Distribute -2: -4y + 10 + 5y = 11
- Combine like terms: y + 10 = 11
- Isolate <em>y</em>: y = 1
<u>Step 3: Solve for </u><em><u>x</u></em>
- Define original equation: x = 2y - 5
- Substitute in <em>y</em>: x = 2(1) - 5
- Multiply: x = 2 - 5
- Subtract: x = -3
The anwser is 3. Because they all can divied by 3
Here, let the age of student be x and teacher be 4x after 28 years, the teacher is double the age of student. So the age of teacher will be 4x+28 and student will be 2(x+28)
So,
4x+28=2(x+28)
4x+28=2x+56
4x-2x=56-28
2x=28
x=14
Therefore the age of the teacher in present will be
=4x+28
=4*14+28
=84
And age of student will be:
=x+28
=14+28
=42
Hope this helps