Hello,
The rate of change is the slope (rise/run, y/x). To find that, we use the equation (y2-y1) over (x2-x1). It means take the second "y" and subtract it from the first "y" and the same to "x". If I plug in the numbers, it would be (3-6) over (5-4), and after you subtract, the answer simplifies to: -3/ 1 which is -3. Yay! We got the slope (rate of change) done.
Now let's find the y-intercept by using the formula of point-slope form,
y-y1= m (slope) (x-x1). This is saying you "y" is subtracted from the first
"y" of the points which equals the slope (m) times the quantity of "x" subtracted by the first "x" of the points.
Let's plug the numbers in: y-6 = -3 (x-4). Let's distribute -3 to the parenthesis, and after that it should simplify to: y-6 = -3x + 12. To get "y" by itself, add 6 to both sides: y = -3x +18. We have finally found the slope-intercept equation for those two points (4,6) and (5,3). To then find the y-intercept in this equation, it would be the 18, because -3 is the slope, so that makes 18 the y-intercept.
In conclusion, the rate of change is -3 and the y-intercept is 18.
I hope this helps!
May
A transformation is rigid if the original shape remains the same shape and size after the transformation.
Flipping a pancake:
After it is flipped, the pancake should stay the same size and shape, so it is a rigid motion and it is a rotation.
Deflating an air mattress:
Deflating a mattress changes its size, so the transformation is not rigid. This is called a dilation.
Moving a clock's minute hand:
Moving the minute hand does not change the hand's size or shape so the transformation is rigid. This transformation is a combination of a translation and a rotation. The translation is what moves the hand around the center of the clock, and the rotation is what changes the direction of the hand.
Enlarging a photo:
Enlarging a photo changes the photo's size, so this transformation is not rigid. This is called dilation.
Putting a golf ball:
Putting does not change the size or shape of a golf ball, so this transformation is rigid. Putting a golf ball both rotates and moves the ball, so the transformation is rotation and translation.
Looking in a car's rear view mirror:
Assuming the car is moving relative to something behind it(because otherwise there would be no transformation), As things come closer to the back of the car, they would appear larger in the mirror, and as things move away from the back of the car, they would appear smaller in the mirror. Because the size changes when looking at the mirror, this is not a rigid transformation and is called dilation.
Answer:
Bag of windflower bulbs costs $8.50
Package of crocus bulbs costs $17.60
Step-by-step explanation:
Let $x be the price of one bag of windflower bulbs and $y be the price of one package of crocus bulbs.
1. Mark sold 2 bags of windflower bulbs for $2x and 5 packages of crocus bulbs for $5y. In total he earned $(2x+5y) that is $105. So,
2x+5y=105
2. Julio sold 9 bags of windflower bulbs for $9x and 5 packages of crocus bulbs for $5y. In total he earned $(9x+5y) that is $164.50. So,
9x+5y=164.50
3. You get the system of two equations:
From the first equation
Substitute it into the second equation:
9x+105-2x=164.50
7x=164.50-105
7x=59.5
x=$8.50
So,
5y=105-2·8.5
5y=105-17
5y=88
y=$17.60
