standard from Ax +By = C
y = 4x+10
subtract 4x from each side
-4x+y = 10
or 4x - y = -10
Answer: it's impossible to obtain 78
Step-by-step explanation: Since the calculator can double any number or permute its digits except 0
starting with number 1
1, 2, 4, 8, 16, 32, 64, 128
Therefore, it's impossible to obtain 78 by a series of these operations
B. 12 would be your answer
Answer: u can research it up
Step-by-step explanation: 210/100 i guess
Answer:

Step-by-step explanation:
The given equation is 
Group similar terms to get:


Square both sides to obtain:


Add 6 to both sides

Simplify the right hand side to obtain;
