A good way to find the answer to these questions is to find it algebraically. Let's call the first number 'n'.
n + (n + 2) + (n + 4) = 54
3n + 6 = 54
3n = 48
n = 16
Therefore the numbers are 16, 18, 20
Answer:
Step-by-step explanation:
One possible system is
1x + 3y = 4
2x + 6y = 8
Note how 2 is twice as large as 1, 6 is twice as large as 3, and 8 is twice as large as 4.
In other words, the second equation is the result of multiplying both sides of the first equation by 2.
1x+3y = 4
2*(1x+3y) = 2*4
2x+6y = 8
Effectively the two equations in bold are the same which produces the same line. The two lines overlap perfectly to intersect infinitely many times. An intersection is a solution.
Answer:
A.
C.
Step-by-step explanation:
A. When adding a negative number to a positive, you subtract. 2.3 - 2.3 will equal 0.
B. When adding two negative numbers, you get an even smaller negative number. (-3.7) + (-4.1) = -7.8
C. When subtracting a negative number, the two negative signs become a positive. -12/4 is equal to 3. -2.6 + 3 is 0.4, which is positive.
D. 5/2 is the same as 2.5. If you subtract 2.5 from 2.5, you will get 0, which is not negative.
E. Two negative signs make a positive, so 72 + 100 is positive, not negative.
Direct variation means their ratio is a constant
x/y is 9/45=1/5
so when x=2, y=5*2=10