2a + 3b = 6
5a + 2b = 4
We multiply the first equation by 5 and the second by 2 and and subtract the second from the first:
10a + 15b = 30
-10a -4b = -8
11b = 22
b = 2
2a + 3(2) = 6
2a = 0
a = 0
Checking,
5(0) + 2(2) = 4
4 = 4, true
Answer:
C is correct
Step-by-step explanation:
do you know why? haha
Answer:
8 minutes
Step-by-step explanation:
The amount in the glass after m minutes can be described by ...
a = 4 + 3/2m
We want to find m when a=16, so ...
16 = 4 + 3/2m
12 = 3/2m . . . . . subtract 4
8 = m . . . . . . . . . multiply by 2/3
It will take 8 minutes to fill the glass.
Answer:
The total value of the given expression is 12.
Step-by-step explanation:
(-2 + 1)² + 5(12 ÷ 3) - 9
First, do the expressions within the parentheses.
(-1)² + 5(4) - 9
Next, simplify the exponents.
1 + 5(4) - 9
Next, multiply 5 by 4.
1 + 20 - 9
Add 1 and 20 together.
21 - 9
Subtract 9 from 21.
12
So, the final answer to this equation is 12.
This is known as Einstein's proof, not because he was the first to come up with it, but because he came up with it as a 15 year old boy.
Here the problem is justification step 2. The written equation
BC ÷ DC = BC ÷ AC
is incorrect, and wouldn't get us our statement 2, which is correct.
For similar triangles we have to carefully pair the corresponding parts to get our ratios right:
ABC ~ BDC means AB:BD = BC:DC = AC:BC so BC/DC=AC/BC.
Justification 2 has the final division upside down.
