Hi there!

First we split up the square root into two parts.

Now we calculate the value of the square roots which have an integer as a solution

Multiplying the integers gives us our next step.

And finally we add up the roots.
Answer:
A = 76.85
B =65.28
Step-by-step explanation:
(30/100)A = 10 + (20/100)B
0.3A - 0.2B = 10 ...... equation (i)
(30/100)B + 35 = (20/100)A
0.2A - 0.3B = 35 ........ equation (ii)
From equation (i)
0.3A = 10 - 0.2B
A = (10 - 0.2b) / 0.3
A = 33.33 - 0.67B ........equation (iii)
Put equation (iii) into equation (ii)
0.2(33.33 - 0.67B) - 0.3B = 35
6.67 - 0.134B - 0.3B = 35
0.434B = 35 - 6.67
B = 28.33 / 0.434
B = 65. 275 = 65.28
Put B = 65.28 into equation (i)
0.3A - 0.2B = 10
0.3A - 0.2(65.28) = 10
0.3A - 13.056 = 10
0.3A = 10 + 13.056
A = 23.056/ 0.3
A = 76.85
The slope is 3 or 3/1 and the Y intercept is 0 or (0,0) because in y=mx+b, is it the slope (3) and b is the y intercept (0)
Greatest error is half smallest measuring unit. It's measured to 0.1 cm , half that is 0.05 cm answer D.