So to find the answer you want to isolate the y. So the first thing you want to do is to move everything to the opposite side of the = sign. You start by adding 10 to both sides.
10+ 5y -10 = -25 +10
5y = -15.
the tens cancel out on the left side and on the right you get left with -15/
Since y is being multiplied by 5 you always want to do the opposite so you divide by 5.
5y/5 = -15/5
y = -3
It's hard to explain but you just have to remember that what you do to one side you must do to the other to keep the equation balanced.
let's set up an equation:
x-4=9
solve normally:
x=13
65% of 39 is 60 the answer is 60
T=34xP
T= tip for him
P= percent he charges for tip
Answer:
a) 4 people ordered streak dinner
b) 3 people ordered chicken dinner
Step-by-step explanation:
Let the number of people that ordered steak dinner be x
and the number of people that ordered chicken dinner be y
From the question,
There are 7 people in your family
Hence, we can write that
x + y = 7 ...... (1)
Also from the question
Some order the chicken dinner for $13 and some order the steak dinner for $18 and the total bill was $111.
We can then write that
13y + 18x = 111 ...... (2)
From equation (1)
x + y = 7
Then,
x = 7 - y ...... (3)
Put this into equation (2)
13y + 18x = 111
13y + 18(7 - y) = 111
13y + 126 - 18y = 111
-5y = -15
5y = 15
y = 15 / 5
y = 3
Put the value of y into equation (3) to get x
x = 7 - y
Then
x = 7 - 3
x = 4
Hence, 4 people ordered streak dinner
and 3 people ordered chicken dinner
a) 4 people ordered streak dinner
b) 3 people ordered chicken dinner