18 students scored 80%
22 students scored 70%
((18 × .8) + (22 × .7)) ÷ .4
(14.4 + 15.4) ÷ .4
(29.8) ÷ .4
74.5
The average score of the whole class was 74.5
X=-2y
1. ( , 0);
2. (9, );
3. ( , -2);
1. (0, 0), as any number multiplied by 0 is 0.
2. x=9, so 9=-2y, y=-4.5 - (9, -4.5)
3. y=-2, so -2y=(-2)*(-2)=4=x - (4, -2)
Solutions: (0, 0), (9, -4.5), <span>(4, -2).</span>
-50 + 18
First, simplify -50 + 18 (a calculator would be best for this problem). / Your problem should look like: -32
Answer: -32 (B)
Answer:
x = 52
General Formulas and Concepts:
Order of Operations: BPEMDAS
Step-by-step explanation:
<u>Step 1: Define equation</u>
3x - 17 = 2x + 35
<u>Step 2: Solve for </u><em><u>x</u></em>
- Subtract 2x on both sides: x - 17 = 35
- Add 17 to both sides: x = 52
<u>Step 3: Check</u>
<em>Plug in x to verify it's a solution.</em>
- Substitute: 3(52) - 17 = 2(52) + 35
- Multiply: 156 - 17 = 104 + 35
- Subtract/Add: 139 = 139