21 sets of nachos =£52.50
56 drinks = £28
= 77 in total =£80.50
System of equations subtraction method
In the addition/subtraction method, the two equations in the system are added or subtracted to create a new equation with only one variable. ... Substitute the variable back into one of the equations and solve for the other variable. Check the solution--it should satisfy both equations.

dividing both sides by -4, we get:

this means, each term is its previous term divided by -4.
now we can construct the sequence as follows:




Answer: the last term is -1/32
So this question is already perfectly set up. Since the 6 and -6 cancel you’ll be left with 5x + 3x which is 8x and -32 + 48 which is 16. 8x=16. Isolate x to get that x=2. Plug 2 back into one of the equations. 5(2) -6y = -32. Solve for y now. -10-32 equals -42. Divide -42 by -6 to get 7. So the final coordinate where the two equations will intersect is (2,7)
Answer:
300 girls were there in the gym.
Step-by-step explanation:
Given:
The ratio of the number of boys to the number of girls was 4:3, after 160 boys left the gym, the ratio became 4:5.
Now, to find the number of girls in the gym.
The girls in the gym does not left, their quantity is same before and after.
So, we multiply the both ratios to make the girls ratio same:
4:3 × 5 = 20:15
4:5 × 3 = 12:15
Now, <em>we find the units of the ratio</em>.
<em>The ratio of boys dropped down by 160</em>:
20 - 12 = 8 units.
160 = 8 units
Now, dividing both sides by 8 we get:
20 = 1 unit
So, 1 unit = 20.
Now, girls = 15 units
So, 15 × 20 = 300.
Therefore, 300 girls were there in the gym.