Answer:
27
Step-by-step explanation:
a + b = 7
a - b = 3
2a = 10
a = 5
b = 7 - 5
b = 2
3⁵ / 3² = 3³ using law of indices
3³ = 27.
Answer:
The answer to your question is y = 2x + 11
Step-by-step explanation:
Data
Original line y = -(1/2)x + 5
Point (-4, 3)
Process
1.- Get the slope of the new line
- Slope of the original line = -1/2
If the lines are perpendicular, the slopes must be reciprocal
-1/2 reciprocal = 2
2.- Get the equation of the new line
y - y1 = m(x - x1)
y - 3 = 2(x + 4)
- Simplification
y - 3 = 2x + 8
- Solve for y
y = 2x + 8 + 3
y = 2x + 11
Answer:
B. 4200
Step-by-step explanation:
A suitable calculator can add the terms for you. (See attached)
__
The first term is 69, and the common difference is 75-69 = 6. The general term is ...
an = a1 +d(n -1)
an = 69 +6(n -1)
Then the 28th term is ...
a28 = 69 +6(27) = 231
The average term is (a28 +a1)/2 = (231 +69)/2 = 150.
The sum is the number of terms multiplied by the average term:
sum = 28×150= 4200
As points, x-intercepts take the form

, so to find the intercepts we can set

and solve for

.

From the first equation alone, we already know that

is a solution, which means one intercept is

.
The second equation gives

so that the second intercept occurs at

.
So if

and

, we have

, giving C as the answer.
Answer:
The volume of the solution with 20% acid is 27 gallons and the one with 10% acid is 18 gallons
Step-by-step explanation:
Myra needs to mix "x" gallons of the solution with 20% and "y" gallons of the solution with 10%. The volume of the final solution must be 45 gallons, therefore:
x + y = 45
The concentration of acid of the final solution is:
0.2*x + 0.1*y = 45*0.16
0.2*x + 0.1*y = 7.2
Therefore we have a system of equation:
x + y = 45
0.2*x + 0.1*y = 7.2
We need to multiply the first equation by -0.1:
-0.1*x -0.1*y = -4.5
0.2*x + 0.1*y = 7.2
We now sum both equation:
0.1*x = 2.7
x = 2.7/0.1 = 27 gallons
y = 45 - 27 = 18 gallons