Answer:
Hello it's me,
I've thought about us for a long, long time,
Maybe I think too much but something's wrong,
There's something here that doesn't last too long,
Maybe I shouldn't think of you as mine.
Step-by-step explanation:
There’s an invisible 1 in front of the minus sign and an invisible 1 in front of the variable.
-1(r+4)=-3 —> -1 times 1r = -1r. -1 times 4 = -4
Multiply inside the parentheses.
-1r-4=-3
Now add 4 to both sides.
-1r-4=-3
+4=+4
-1r = 1
Now divide
R= -1
3/7 = 9/x
cross multiply because thats how u solve proportions
(3)(x) = (7)(9)
3x = 63
x = 63/3
x = 21
and if u will notice : 3/7 and 9/21 ....9/21 reduces to 3/7....so these are equivalent fractions...because proportions are nothing but equivalent fractions