Standard deviation I think
I hope it workssssssssssssssssssssss.
Range is ] -20 , -10 [
both points are disclude according to the empty circle
Answer:
(3, -6)
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>Algebra I</u>
- Coordinates (x, y)
- Terms/Coefficients
- Solving systems of equations using substitution/elimination
Step-by-step explanation:
<u>Step 1: Define Systems</u>
y = 4x - 18
y = -5x + 9
<u>Step 2: Solve for </u><em><u>x</u></em>
<em>Substitution</em>
- Substitute in <em>y</em> [2nd Equation]: 4x - 18 = -5x + 9
- [Addition Property of Equality] Add 5x on both sides: 9x - 18 = 9
- [Addition Property of Equality] Add 18 on both sides: 9x = 27
- [Division Property of Equality] Divide 9 on both sides: x = 3
<u>Step 3: Solve for </u><em><u>y</u></em>
- Substitute in <em>x</em> [1st Equation]: y = 4(3) - 18
- Multiply: y = 12 - 18
- Subtract: y = -6
Answer:
Step-by-step explanation:
Let the speed of Masha = s, speed of Dasha = d
- Distance = 20 km
- Time difference = 20 min = 1/3 hr
- Speed difference = 2 km/h
<u>As per above info we get following equations:</u>
- s = d + 2
- 20/s + 1/3 = 20/d
<u>Substitute s and solve for d:</u>
<u>Get rid of fraction by multiplying all terms by 3d(d + 2):</u>
- 60d + d(d + 2) = 60(d + 2)
- 60d + d² + 2d = 60d + 120
- d² + 2d = 120
- d² + 2d + 1 = 121
- (d + 1)² = 11²
- d + 1 = 11
- d = 10
<u>Find s:</u>
<u>The answer is</u>
- Masha's speed 12 km/h and Dasha's speed 10 km/h