2x+3y = -33 3x+6y=-57 using elimination

1 answer:

4 0

$\left\{\begin{array}{ccc}2x+3y = -33&\text{multiply both sides by 3}\\3x+6y=-57 &\text{multiply both sides by (-2)}\end{array}\right\\\\\underline{\left\{\begin{array}{ccc}6x+9y=-99\\-6x-12y=114 \end{array}\right}\qquad\text{add both sides of the equations}\\.\qquad-3y=15\qquad\text{divide both sides by (-3)}\\.\qquad y=-5\\\\\\\text{Put the value of y to the first equation}\\\\2x+3(-5)=-33\\2x-15=-33\qquad\text{add 15 to both sides}\\2x=-18\qquad\text{divide both sides by 2}\\x=-9$

$Answer:\ x=-9\ and\ y=-5\to(-9,\ -5)$

You might be interested in

You and your friends decide to go to the movies. Each movie, m, costs $10. If each movie costs $10. What is the total cost for a

alexira [117]

Answer:

6x10=60

Step-by-step explanation

each person is giving $10 to see a movie, you multiple it

4 0

3 years ago

Divide.<br> 14pq4 7p4q4<br> 8r3<br> 2r

svet-max [94.6K]

Dividing is changed to multiplication by inverting the second fraction. So:

7 0

2 years ago

The equation y=9. 5x 0. 4 represents the line of best fit for the distance (in feet) that Marcella traveled over time (in second

Bas_tet [7]

The average speed of Marcella in feet per seconds is 9.5 feet per second.

<h3>How are time taken for travel, distance traveled, and the average speed are related?</h3>

We have this below shown relation between them

$\text{Average speed} = \dfrac{\text{Distance traveled}}{\text{Total time taken to travel that distance}}\\\\or\\\\\text{Total time taken to travel that distance}= \dfrac{\text{Distance traveled}}{\text{Average speed} }$

For the given case, we have:

The equation $y=9.5x + 0.4$ represents the line of best fit for the distance (in feet) that Marcella traveled over time (in seconds)

The line of best fit can be taken as approximately telling about the data points ( y = distance traveled in feet, and x = time spent )

Let the initial time be 'x' with initial distance traveled 'y', then the time after one second will be (x+1), and the distance traveled be $y_1$

The value of y and $y_1$ are calculated as:

$y = 9.5x + 0.4\\y_1 = 9.5(x+1) + 0.4 = 9.5x + 9.9$

Thus, the average speed is calculated at time 'x' as:

$\text{Average speed} = \dfrac{\text{Distance traveled}}{\text{Total time taken to travel that distance}}\\\\or\\\\\text{Average speed} = \dfrac{y_1 - y}{x + 1 - x} = \dfrac{9.5x + 9.9 - 9.5x - 0.4}{1} = 9.5 \: \rm feet/sec$