Solve for y:
3x = 7y + 21
~Subtract 7y to both sides
3x - 7y = 21
~Subtract 3x to both sides
-7y = 21 - 3x
~Divide -7 to both sides
y = -3 + 3/7x
~Change order
y = 3/7x - 3
Best of Luck!
Answer:
-10/3 or -3.33
Step-by-step explanation:
substitute 0 for y
0 = 6x + 20
-20 = 6x + 20 - 20 subtract 20 on both sides
-20 = 6x divide by 6 on each side
-20/6 = 6x/6
x = -20/6 simplify
x = -10/3
Answer:



Step-by-step explanation:
3) Area of a circle is

Where r = 6
Thus,




4) False
Area of a circle is measured by the formula below:

5) The formula for calculating the area of a rectangle is given thus:

Where, l = 10ft; w = 7ft

Answer: Option C) Raj forgot the negative when substituting -15+9x for y.
Solution:
(1) 9x-y=15
(2) 2x+8y=28
Isolating y in the first equation. Subtracting 9x both sides of the equation:
(1) 9x-y-9x=15-9x
Subtracting:
(1) -y=15-9x
Multiplying both sides of the equation by -1:
(1) (-1)(-y)=(-1)(15-9x)
(1) y=-15+9x
Then Raj found the value of y. It's not option D.
Substitutng y by -15+9x in the second equation:
(2) 2x+8(-15+9x)=28
Then option C) is the answer: Raj forgot the negative when substituting -15+9x for y.
Eliminating the parentheses applying the distributive property in the multiplication:
(2) 2x-120+72x=28
Adding similar terms:
(2) 74x-120=28
Solving for x. Adding 120 both sides of the equation:
(2) 74x-120+120=28+120
Adding:
(2) 74x=148
Dividing both sides of the equation by 74:
(2) 74x/74=148/74
Dividing:
(2) x=2
Solving for y: Replacing x by 2 in the first equation:
(1) y=-15+9x
(1) y=-15+9(2)
Multiplying:
(1) y=-15+18
Subtracting:
(1) y=3