Answer:
4
Step-by-step explanation:
To find the number you have to reverse the equation
Let us call the number "x"
x + 9 = 13
So to find x we flip the equation
13 - 9 = x
Solve it
4 = x
So the missing number is 4
Answer:
a·a-b·b
Step-by-step explanation:
Answer:
x = -2
Step-by-step explanation:
Answer:
5√3 / 2
Step-by-step explanation:
tan 30 = ( 5 / 2 ) / y
1 / √3 = 5 / 2y
2y = 5√3
y = 5√3 / 2