Answer:
7
Step-by-step explanation:
12-7=5
or
5+7=12
The rule is 3^x.
Check: 3^1 = 3; 3^2 = 9; 3^3 = 27 and 3^4 = 81
Answer:
6x+15
Step-by-step explanation:
Length of the outer frame: 4+2x
width of the outer frame: 3+2x
area of the outframe: (4+2x)(3+2x)=15
expand the equation: 12+8x+6x+12x^2=15
combine like terms: 4x^2+14x-3=0
