y = 5 x + 100
your brother has the sign of the slope wrong
your brother has the sign of the slope wrong
In the context of a linear equation (y = mx + b), the y-intercept (b) represents the value of y when x is equal to 0. In this case, the y-intercept is 100, which means that the initial value of y (or the quantity in the situation) is 100 when x (or the time in the situation) is 0.
The slope (m) represents the rate of change of y with respect to x. In other words, it indicates how much y changes for each unit increase in x. In this case, the slope is 5, indicating that for every unit increase in x (month), the quantity (y) decreases by 5.
Therefore, the correct interpretation of the given linear equation (y = 5x + 100) in the context of your partner's situation would be that your younger brother initially had 100 building blocks, and he loses 5 of them every month.