Question

an electrician has $120 to spend on interior light fixtures. The wholesale price for a 13-watt low-energy lamp is $4. The price for a high-energy lamp is $5. 1)Write the algebraic expression for how much the electrician spends for a units of the low -energy of the low-energy lamp and b units of the high-energy lamp. 2)Write an equation that relates your answer to Exercise 1 to the amount of money the electrician has to spend.

Answer 1

X = low-energy lamp
y = high-energy lamp

1) 4x + 5y

2) 120= 4x + 5y

Answer 2

Ok, are you ready? Here we go:
First we know that he has 120 dollars, so the first part of the equation is 120 = ?
it equals something, we dont know, so lets find out.
low energy lamp: 13 dollars per unit
High Energy Lamp: 14 dollars per unit
So, 13a (a stands for "a units") and 14b ( b stands for "b units) are the respective equation for the given values, that's question 1
Question 2, we connect the 120 values and the 2 equation we made, so 13a +14b = 120 dollars