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
notice that, if Q is the midpoint of PR, that simply means that PQ = QR = 43.
![\bf \boxed{P}\underset{\leftarrow 9x-31 \to }{\stackrel{\stackrel{\downarrow }{43}}{\rule[0.35em]{10em}{0.25pt}}Q\stackrel{43}{\rule[0.35em]{10em}{0.25pt}}}\boxed{R} \\\\\\ 9x-31=43+43\implies 9x-31=86\implies 9x=117 \\\\\\ x=\cfrac{117}{9}\implies x=13](https://tex.z-dn.net/?f=%5Cbf%20%5Cboxed%7BP%7D%5Cunderset%7B%5Cleftarrow%209x-31%20%5Cto%20%7D%7B%5Cstackrel%7B%5Cstackrel%7B%5Cdownarrow%20%7D%7B43%7D%7D%7B%5Crule%5B0.35em%5D%7B10em%7D%7B0.25pt%7D%7DQ%5Cstackrel%7B43%7D%7B%5Crule%5B0.35em%5D%7B10em%7D%7B0.25pt%7D%7D%7D%5Cboxed%7BR%7D%0A%5C%5C%5C%5C%5C%5C%0A9x-31%3D43%2B43%5Cimplies%209x-31%3D86%5Cimplies%209x%3D117%0A%5C%5C%5C%5C%5C%5C%0Ax%3D%5Ccfrac%7B117%7D%7B9%7D%5Cimplies%20x%3D13)
I could answer this if you could tell me the value of one of the letters
Step-by-step explanation:
√(m + n) = √m + √n
Square both sides:
m + n = m + 2√(mn) + n
Simplify:
0 = 2√(mn)
mn = 0
The equation is only true if either m or n (or both) is 0.