Answer:
B
Step-by-step explanation:
A. these simply to 21 + 7x and 21 + 3x
- this one is incorrect because the 7x and 3x are different
B. these simplify to 10 + x and 10 + x
- this is the correct one since they are exactly the same
C. these simplify to 21x and 7x + 21
- these two are not the same because one expression has only a number with a variable but the other one has a number with a variable <em>and </em>another number
D. these simplify to 
and 
- in subtraction, the order of the 3 and the x matters, so the equations are not the same
- example: 6 - 4 = 2 but 4 - 6 = -2
Answer:
g(x)=−4x^2 and m(x)=4x^2
Step-by-step explanation:
A horizontal stretch or shrink happens when you multiply the parent function (in this case f(x) = x²) by a number. If this number is between 0 and 1, the graph will be stretched horizontally. If this number is greater than 1, the graph will be shrunk horizontally. If the number is between -1 and 0, the graph will be stretched horizontally and flipped; if the number is less than -1, the graph will be shrunk horizontally and flipped.
The graphs that are horizontally shrunk are steeper than the others. This is m(x)=4x^2 and g(x) = -4x^2.
Answer:
y = 3x - 16
Step-by-step explanation:
We are asked to find the equation of the line perpendicular to 2x + 6y = 30
We can use two formulas for this question, either
y = mx + c. Or
y - y_1 = m(x - x_1)
Step 1: calculate the slope
From the equation given
2x + 6y = 30
Make y the subject of the formula
6y = 30 - 2x
Or
6y = -2x + 30
Divide both sides by 6, to get y
6y/6 = ( -2x + 30)/6
y = (-2x + 30)/6
Separate them in order to get the slope
y = -2x/6 + 30/6
y = -1x/3 + 5
y = -x/3 + 5
Slope = -1/3
Step 2:
Note: if two lines are perpendicular to the other, both are negative reciprocal of each other
Perpendicular slope = 3/1
Substitute the slope into the equation
y = mx + c
y = 3x + c
Step 3: substitute the point into the equation
( 6,2)
x = 6
y = 2
2 = 3(6) + c
2 = 18 + c
Make the c the subject
2 - 18 =c
c = 2 - 18
c = -16
Step 4: sub the value of c into the equation
y = 3x + c
y = 3x - 16
The equation of the line is
y = 3x - 16
If you try out the other formula, u will get the same answer
Shorter <span>piece = x
longer </span><span>piece = 4x
x + 4x = 48.5
5x = 48.5
x = 48.5/5
x = 9.7 cm </span>← shorter piece
longer piece = 4x = 4 * 9.7 = 38.8 cm
