Answer:
A)
Step-by-step explanation:
To find the answer we must solve each of the systems separately. Starting with the first one:
x + y = 2
2x - y = 10
We must find what x or y is equal to and then replace it in the second equation. I'll go with y as it seems easier:
x + y = 2
y = 2 - x
Now that we found y we replace it in the second equation this way. Be careful with the signs, the minus with change our signs:
2x - (2 - x) = 10
2x - 2 + x = 10
3x = 12
x = 12/3
x = 4
Now that we have x, we replace the variable with its value in one of the equations. Again, for simplicity I'll go with the one that seems easier.
4 + y = 2
y = 2 - 4
y = - 2
Answer:
C
Step-by-step explanation:
Answer:
it is B.
Step-by-step explanation:
B. can i have brainlyest please
Answer:
There are 123,410 ways
Step-by-step explanation:
The number of ways or combinations in which we can select k elements from a group of n elements is given by:

In this case, we can replace n by 43 and k by 4, because we are going to select 4 light bulbs from a batch of 43 light bulbs.
So, the number of combinations is calculated as:

It means that there 123,410 ways to select 4 light bulbs from a batch of 43 lights bulbs to be tested for defects
Answer: 2.4 * 10^6
Step-by-step explanation: What you need to do in order to find the solution is, as you can see in 2,400,000, Just remove all of the zeroes, each zero adds on an exponent number to the 10. Remove 3 zeroes and it becomes 10^3. Remove 4 zeroes and it becomes 10^4. It is 2.4 because you only want to have one value above the decimal point.