Answer:
12=12
Step-by-step explanation:
2a = b
a -3b =12
To solve, set one of the equations equal to zero. The first equation is actually already set to 0.
b = 2a
Now you can plug this equation into the other one, by substituting the b in the equation with this.
a -3b = 12
a – 3(2a) = 12
Now all you have to do is distribute the 3 (multiply the number outside the parenthesis, 3 in this case, by everything inside).
a – 6a = 12
Combine like terms. Since we have 1 positive a and 6 negative ones, we subtract the two numbers without the signs
6-1 = 5
And take the sign of the larger number. Since 6 is large and 6 is negative, we are left with
-5a = 12
Now solve for a, which in this case means dividing both sides by -5
a = -12/5
Simplify
a = -2.4
Now that you have a, it’s easy to find b
b = 2a
b = 2(-2.4)
b= -4.8
Now you check your work by plugging your new a and b into either equation to see if it’s true.
-4.8 = 2(-2.4)
-4.8 = -4.8
And just for laughs let’s try the other equation
a -3b =12
-2.4 – 3(-4.8) = 12
Distribute the 3 again. Remember that when two negative numbers are multiplied they become positive.
-2.4 +14.4 = 12
12 = 12
Answer:
the answer is 48
Step-by-step explanation:
I think its 149/ 490. Not sure, but pretty confident. Hope this helps.
Answer: The formula is x6
Step-by-step explanation:
Answer:
down below
Step-by-step explanation:
1) 4% of 120 = 4.8, so 120+4.8 = 124.8 cm tall
2) 12% of 6000 = 720 . 6000-720 = 5280 gallons
3) 22% of 200 = 44 . 200-44 = 156
4) 30% of 40 - 12 . 40 - 12 = $28
5) 35% of 140 = $49 . 140 + 49 = $189
