Answer: x=3
Step-by-step explanation:
to make y=-4 from -12 you have to divide by 3. so divide the 9 by 3 to get 3 which is your answer
Answer:
x=-1 and y=-5
Step-by-step explanation:
ሰላም!
Given expressions let them given as two equations
- y=2+7x....... equation (1)
- -2x+6y=-28..... equation (2)
Thus, substitute y=2+7x into equation (2)
simplify it
subtract 12 from both sides
divide both sides by 40
Therefore, as we get the value of x=-1 substitute it to equation (1) and solve for variable y
To be more sure make a cross check on both of the two expressions
Thus,
1) y=2+7x .... substitute y=-5 and x=-1 and check if it is equal
-5=2+7(-1)
-5=2-5
-5=-5
2)-2x+6y=-28... substitute and check
-2(-1)+6(-5)=-28
2-30=-28... (-a)(-b)=ab
-28=-28
Hope it helps!
Answer:
see explanation
Step-by-step explanation:
To prove that BC ≅ AD, that is that BC = AD
You would need to prove the lengths are the same.
Answer:
1 hour each 30 minutes so the answer is 30 minutes
If Sandra mixes <em>x</em> L of 65% solution with <em>y</em> L of 90% solution, then the resulting mixture has a total volume of
<em>x</em> + <em>y</em> = 500
litres, and it contains
0.65<em>x</em> + 0.90<em>y</em> = 0.75 (500) = 375
litres of alcohol.
Solve the first equation for <em>y</em> :
<em>y</em> = 500 - <em>x</em>
<em />
Substitute this into the second equation and solve for <em>x</em> :
0.65<em>x</em> + 0.90 (500 - <em>x</em>) = 375
0.65<em>x</em> + 450 - 0.90<em>x</em> = 375
75 = 0.25<em>x</em>
<em>x</em> = 300
Solve for <em>y</em> :
<em>y</em> = 500 - 300
<em>y</em> = 200
So, Sandra should mix 300 L of 65% solution with 200 L of 90% solution.