openThe equation must be
y = 6 x + 120
The slope is 6 and the y-intercept is 120
The mistake is
He chooses a -ve slope because he said he will loss 6
Loss means (-) and the value will decrease
So the real-world situation is
I opened a saving account with $120 worth of birthday money and I have $6 a month
Choose add
They want us to correct the wrong
So we must say positive slope and increasing