Answer:
Two straight lines with slopes m and m' are parallel when m = m'
Two straight lines with slopes m and m' are perpendicular when m × m' = - 1.
Step-by-step explanation:
Let us assume that the two non-vertical lines in the slope-intercept form are
y = mx + c ........... (1) and
y = m'x + c' ............ (2)
If those two lines are parallel then we can say the slope of them will be the same i.e. m = m'
Now, if given two straight lines (1) and (2) are perpendicular to each other and neither of them is parallel to the axes, then we can write m × m' = - 1. (Answer)
-> 40 hours per week, 52 weeks a year
<u>shop and save grocers</u>
monthly wages: $3,800
hourly wages: $3800 / 160 = $23.75 per hour
yearly wages: $23.75 per hour x 40 hours per week x 52 weeks a year
= $49,400
<u>unbelievable toys</u>
yearly wages: $43,000
<u>convenience store</u>
$16.50 per hour x 40 hours per week x 52 weeks a year
= $34,320
49,400 - 34,320 = 15,080
..? that's not even an answer choice what-
2x+4 is the length of one side
Answer:
<em>The ball's speed will be 10 m/s at t=1.22 seconds</em>
Step-by-step explanation:
The vertical motion of an object is controlled by the force of gravity. This means that there is a non-zero net force acting on the object that makes it accelerate downwards.
If the object is thrown upwards at speed vo, its speed at time t is:

Where g is the acceleration of gravity 
Our ball is thrown upwards with v0=22 m/s. We need to calculate the time when its speed is vf=10 m/s.
Solving the above equation for t:

Substituting:

t=1.22 seconds
The ball's speed will be 10 m/s at t=1.22 seconds