Chapter SH, Problem 14.5.3EP

To determine

To find: The Product of the given numbers

Answer to Problem 14.5.3EP

The Product of $(a+4)(a-1)$ is $a^2+3a-4$

Explanation of Solution

Given:

  $(a+4)(a-1)$

Calculation:

By using the FOIL method

The first terms are $a,a$

Product of first two terms is $a\times a=a^2$

The outer terms are $a,-1$

Product of outer terms is $a(-1)=-a$

The inner terms are $4,a$

Product of inner terms is $4\times a=4a$

The last terms are $4,-1$

Product of last terms is $4(-1)=-4$

By adding all the products

  $(a+4)(a-1)=a^2-a+4a-4$

  = $a^2+3a-4$ (simplify)

Conclusion:

Hence, the Product of $(a+4)(a-1)$ is $a^2+3a-4$