Just plug in the numbers for the variables.
20+3(8)+17(2)=
2x - 2y = -12
4x - 7y = -15
Multiply the first equation by -2 to make the 2x the opposite of 4x:
2x - 2y = -12 x -2 = -4x + 4y = 24
Now add this to the second equation:
-4x + 4y = 24 + 4x - 7y = -15:
-3y = 9
Divide both sides by -3
y = 9 / -3
y = -3
Now you have Y, replace y in one of the equations and solve for x:
2x - 2(-3) = -12
2x +6 = -12
Subtract 6 from both sides:
2x = -18
Divide both sides by 2:
x = -18 /2
X = -9
Check:
2(-9) - 2(-3) = -12
-18 + 6 = -12 TRUE
4(-9) - 7(-3) = -15
-36 +21 = -15 TRUE
X = -9, y = -3
(-9,-3)
Answer:
4/9
Step-by-step explanation:
Let the amount of 95% sol = a ml and
the amount of 30% sol = b ml.
So, the total amount of the compound=a+b=500 ml
As the compound is 50% solution, so
95% of a + 30% of b= 50% of (a+b)
(95/100)a+(30/100)b=(50/100)(a+b) [from equation (i)]
95a + 30b = 50(a+b)
95(a/b)+30 = 50(a+b)/b [dividing both sides by b]
95(a/b)+30 = 50(a/b+1)
95(a/b)+30 = 50(a/b)+50
95(a/b)-50(a/b)=50-30
45(a/b)=20
a/b=20/45
a/b=4/9
Therefore, a:b=4:9
As a+b= 500 ml, so the amount of 95% sol = 
ml
and the amount of 95% sol = 
ml
Hence, the proportion of 95% sol and 30% sol to make a compound of 50% sol must be 4/9.
Answer: 1.37
Step-by-step explanation:
so to find out how far molly walked you have to find out how far her sister and brother walked combined 1.23+0.85=2.08 then subtract 3.45-2.08 to get 1.37
molly waled 1.37 more miles then her brother and sister combined
Answer:
A. (7, 27)
Step-by-step explanation:
Given that we have the point (20,27) the only choice that works is A as (20,27) marks the bottom of the triangle
Hope this helped!
