Solution:
Given;


Thus, the yearly interest rate on Bianca's account is 2.4%
Answer: x=2
Step-by-step explanation: The axis of symmetry is the x-axis of the vertex which in this case is (2, -1)
Answer:
The first equation must be multiplied by -5 to eliminate x variable by addition
Step-by-step explanation:
4 x - 3 y = 1 (1)
5 x + 4 y = 9 (2)
If the second equation is multiplied by 4
5x+4y=9. ×4
We have,
20x+16y=36 (3)
The first equation should be multiplied by -5 to eliminate x variable by addition
4x-3y=1 × -5
We have
-20x+15y=-5 (4)
Add equation (3) and (4) to eliminate x variable
20x+16y=36
-20x+15y=-5
31y=31
Divide both sides by 31
y=1
Substitute y=1 into equation (1)
4 x - 3 y = 1
4x-3(1)=1
4x-3=1
4x=1+3
4x=4
Divide both sides by 4
x=1
Short Answer: 18 minutes
Remark
The answer to this problem is less than the smallest time of the two people working together. that fact lets out C and D (38 minutes and 75 minutes). Now you have to choose 15 minutes and 18 minutes. There's a method. No guessing needed.
Givens
Let the time for Sophie = S
Let the time for Simon = M
Let the job to completion = 1
S = 45 minutes
M = 30 minutes
Step One
Convert minutes to hours.
45 minutes = 45 / 60 = 3/4 hour = 0.75 hour
30 minutes = 30 / 60 = 1/2 hour = 0.50 hour
Step Two
Set up the Equation
The formula is a form of job / hour.
Let the time = t that they both have to work
job = 1 in these problems.
1/S + 1/M = 1/t
1/0.75 + 1/0.5 = 1/t
Solve
1 ÷ 0.75 = 1.33333
1 ÷ 0.5 = 2
1.3333 + 2 = 3.33333
3.3333 = 1 / t Multlply both sides by t
3.3333*t = 1
t = 1 / 3.333333333
t = 0.3 of an hour
1 hour = 60 minutes
0.3 hours = x Cross Multiply
x = 60 * 0.3
x = 18 minutes
Answer working together it took them 18 minutes <<<<<
The answer to the math problem is 8y^12