Answer:
Step-by-step explanation:
The formula of a slope:
If
m > 0, then a line is rising
m < 0, then a line is falling
m = 0, then a line is horizontal
m is undefined, then a line is vertical
<h2>a.</h2>
(2, 1) and (4, 5)
<h2>b.</h2>
(-1, 0) and (3, -5)
<h2>c.</h2>
(2, 1) and (-3, 1)
<h2>d.</h2>
(-1, 2) and (-1, -5)
<span>5x-6y=-15
5x+6y=12
---------------add
10x = -3
x = -3/10
x = -0.3
</span>5x+6y=12
5(-0.3) + 6y = 12
6y = 12 + 1.5
6y = 13.5
y = 13.5 / 6
y = 2.25
Answer:
The number of liters of 25% acid solution = x = 160 liters
The number of liters of 40% acid solution = y = 80 liters
Step-by-step explanation:
Let us represent:
The number of liters of 25% acid solution = x
The number of liters of 40% acid solution = y
Our system of Equations =
x + y = 240 liters....... Equation 1
x = 240 - y
A 25% acid solution must be added to a 40% solution to get 240 liters of 30% acid solution.
25% × x + 40% × y = 240 liters × 30%
0.25x+ 0.4y = 72...... Equation 2
We substitute 240 - y for x in Equation 2
0.25(240 - y)+ 0.4y = 72
60 - 0.25y + 0.4y = 72
Collect like terms
- 0.25y + 0.4y = 72 - 60
0.15y = 12
y = 12/0.15
y = 80 Liters
Solving for x
x = 240 - y
x = 240 liters - 80 Liters
x = 160 liters
Therefore,
The number of liters of 25% acid solution = x = 160 liters
The number of liters of 40% acid solution = y = 80 liters
The answer is 7.3, If you use the order of operations, When you divide 58.4 by 8 you get 7.3
