Answer: A
Explanation: multiply 128 by .85
Answer:
She bought 6 erasers.
Step-by-step explanation:
Answer:
The other side was decreased to approximately .89 times its original size, meaning it was reduced by approximately 11%
Step-by-step explanation:
We can start with the basic equation for the area of a rectangle:
l × w = a
And now express the changes described above as an equation, using "p" as the amount that the width is changed:
(l × 1.1) × (w × p) = a × .98
Now let's rearrange both of those equations to solve for a / l. Starting with the first and easiest:
w = a/l
now the second one:
1.1l × wp = 0.98a
wp = 0.98a / 1.1l
1.1 wp / 0.98 = a/l
Now with both of those equalling a/l, we can equate them:
1.1 wp / 0.98 = w
We can then divide both sides by w, eliminating it
1.1wp / 0.98w = w/w
1.1p / 0.98 = 1
And solve for p
1.1p = 0.98
p = 0.98 / 1.1
p ≈ 0.89
So the width is scaled by approximately 89%
We can double check that too. Let's multiply that by the scaled length and see if we get the two percent decrease:
.89 × 1.1 = 0.979
That should be 0.98, and we're close enough. That difference of 1/1000 is due to rounding the 0.98 / 1.1 to .89. The actual result of that fraction is 0.89090909... if we multiply that by 1.1, we get exactly .98.
Answer:
y = 3/2x - 5
Step-by-step explanation:
To find the equation of the line
Step 1: find slope
( 2 , -2) ( 4 , 1)
x_1 = 2
y_1 = -2
x_2 = 4
y_2 = 1
Insert the values into
m = (y_2 - y_1) / (x_2 - x_1)
m = ( 1 - (-2) / (4 - 2)
= ( 1 + 2) / ( 4 -2 )
= 3 / 2
m = 3/2
Step 2: substitute m into the equation
y = mx + c
y = 3/2x + c
Step 3: substitute any of the two points into the equation
Let's pick (4 , 1)
x = 4
y = 1
y = 3/2x + c
1 = 3/2(4) + c
1 = 3*4/2 + c
1 = 12/2 + c
1 = 6 + c
1 - 6 = c
c = 1 - 6
c = -5
Step 4 : substitute c into the equation
y = 3/2x + c
y = 3/2x - 5
The equation of the line is
y = 3/2x - 5
