if you didnt know, there is always an invisable 1 before the parentheses unless there is a number there. so think about it as -4 + 1(-6). then, -6 times 1 is still -6.
You just do pemdas (parentheses, equation, multiplication, division, adding, subtracting) so you obviously start with -6 and add that to -4 which gives you -10 :)
