Answer:
Jake's error in step 3
Step-by-step explanation:
we have

Complete the square
step 1
Group terms that contain the same variable, and move the constant to the opposite side of the equation

step 2
Complete the square. Remember to balance the equation by adding the same constants to each side


step 3
Rewrite as perfect squares

Jake's error in step 3
He placed 6 instead of 3 in the left side
step 4
take square root both sides

step 5

step 6

step 7
x=5 and x=1
Answer:
(0,3) and (5,0)
Step-by-step explanation:
Set of equations that can be used to calculate rate for each plumber:
2A+8B+8C = 1,400 --- (1)
4A+7B+10C = 1,660 --- (2)
3A+9B+9C = 1,660 --- (3)
------------------------------------
2*(1) - (2)
------------------------------------
4A+16B+16C = 2,800
4A+7B+10C = 1,660 -
------------------------------------
9B+6C = 1,140 --- (4)
------------------------------------
3(2) -4(3)
-----------------------------------
12A+21B+30C = 4,980
12A+36B+36C = 6,600 -
-----------------------------------
-15B-6C = -1,620 --- (5)
------------------------------------
(4) + (5)
------------------------------------
9B+6C = 1140
-15B-6C = -1620 +
-------------------------------------
-6B = -480 => 6B = 480 => B = 480/6 = 80
-------------------------------------------------------
Using (4), 9(80)+6C = 1140
720+6C = 1140 => 6C = 1140-720 = 420 => C = 420/6 = 70
------------------------------------------------------------------------------
Using (1), 2A+8(80)+8(70) = 1400
2A+640+560 =1400 => 2A = 1400-640-560 = 200 => A = 200/2 = 100
----------------------------------------------------------------------------------------------
The rates are:
A = $100
B = $80
C = $70
--------------------------------
On Thursday, number of calls: A = 4 hrs, B = 6 hrs, C = 3 hrs
Money earned = 4*100+6*80+3*70 = $1,090
Answer:
f = 
Step-by-step explanation:
1. 4(4f - 9) = -(2-f) distribute the negative
2. 4(4f - 9) = -2 + f Distribute the 4
3. 16f - 9 = -2 + f Subtract f on both sides
4. 15f - 9 = -2 Add 9 on both sides
5. 15f = 7 Divide both equations by 15
6.
f = 
Answer:
(1,3) should be the answer due to the fact that both lines intersect at that point.
Step-by-step explanation: