Answer:
robert is 12 years old
Step-by-step explanation:
robert's age=x
40=3x+4
that's the equation
40=3x+4
=36=3x
x=12
You forgot to put the decimal in there so i could round it
You can use the SSS, SAS, ASA, AAS congruency for any triangles and the HL congruency for just the right triangle
The answer to the question is 13
The surface area will increase by a factor of 49/16