Answer:
[tex]A. \ a = (\frac{m}{m}\times \frac{a_1}{1}) + (\frac{1}{1}\times \frac{F}{m})[/tex]
Explanation:
Given the expression for calculating the acceleration as shown;
[tex]a = a_1 + \frac{F}{m}[/tex] where;
[tex]a_1 = 3.00m/s^2\\\\F = 12.0kg.m/s^2\\\\m = 7.00kg\\[/tex]
To get the correct step for obtaining a common denominator for the two fractions in the expression in solving for a, we will find the LCM of the given expression as shown;
[tex]a = a_1 + \frac{F}{m}\\\\a = \frac{a_1}{1}+\frac{F}{m}\\ \\a = \frac{(m*a_1)+F}{m} \\\\a = \frac{ma_1+F}{m}\\ \\a = (\frac{m}{m}\times \frac{a_1}{1}) + (\frac{1}{1}\times \frac{F}{m})[/tex]
The final expression gives the requires step. On substituting the given parameters into the resulting expression to get a;
[tex]a = (\frac{7}{7}\times \frac{3}{1}) + (\frac{1}{1}\times \frac{12}{7})\\\\a = \frac{21}{7} + \frac{12}{7}\\ \\a = \frac{21+12}{7}\\ \\a = \frac{33}{7} m/s^2[/tex]
