Step-by-step explanation:
what did it mean to have an x-(axis-)intercept ?
just imagine the function curve gets closer and closer to the x-axis, and then finally intersects it.
that means there is a point on this function that is also on the x-axis.
what are the coordinates of points on the x-axis ?
well, sure, for x any value from -infinity to +infinity is possible.
but what about y ? what values can y have for points on the x-axis ? greater than 0 ? lower than 0 ?
no, if y would have any value different than 0, this point would not be ON the x-axis.
so, we know, the interception point must have y = 0.
and that is what we use in our function equation :
0 = 3 - 5x
5x = 3
x = 3/5
so, at x=3/5 there is the x-interception with the point coordinates (3/5, 0).
