Answer: The answer is (B) 2x + 3(3x – 5) = 51
.
Step-by-step explanation: We are given three options and we are to select which choice shows the result of substituting 3x – 5 into the second equation for y.
So, y = 3x - 5.
Since the standard form of a linear equation i two variables is ax + by = c, so the second equation as given in the options must be of the form 2x + 3y = 51.
If we substitute y = 3x - 5, then this equation becomes
2x + 3(3x - 5) = 51.
Thus, (B) 2x + 3(3x – 5) = 51 is the correct option.
Answer: you bought 9 burgers and 16 tacos
Step-by-step explanation:
Let x represent the number of burgers that you bought.
Let y represent the number of tacos that you bought.
You buy a total of 25 burgers and tacos. It means that
x + y = 25
The burgers cost $3.50 each and the tacos cost $2.25 each. The total cost of the burgers and tacos that you bought is $67.50. It means that
3.5x + 2.25y = 67.5- - - - - - - - - - - - 1
Substituting x = 25 - y into 1, it becomes
3.5(25 - y) + 2.25y = 67.5
87.5 - 3.5y + 2.25y = 67.5
- 3.5y + 2.25y = 67.5 - 87.5
- 1.25y = - 20
y = - 20/ - 1.25
y = 16
x = 25 - y = 25 - 16
x = 9
A = 180 - 143 = 37
b = 143
c = a = 37
e = a = 37
f = 90 - 37 = 53
d = 180 - 85 - 37 = 58
g = 48
h = 180 -48 -48 = 84
k = 180 -84 = 96
m = 180 - 58 - 96 = 26
p = 180 - 26 - 85 = 69
r = 180 -69 = 111
s = p = 69
