Question

If A = r – 2 and B = r^2 – 4r + 5, find an expression that equals 3A + 2B in standard form.

Answer 1

Answer:  2r² - 5r + 4

Step-by-step explanation:

Since expression = 3A + 2B                             [subsitute in values of A&B]

       ⇒                  = 3(r – 2) + 2(r² – 4r + 5)     [expnad the brackets]

                            = 3r - 6 + 2r² - 8r + 10           [group like terms ins stan. form]

                            = 2r² - 8r +  3r + 10 - 6         [simplify like terms]

                            = 2r² - 5r + 4

Note:

Standard form is ax² + bx + c  (where x is any variable, in this case 'r', and a,b,c are the coefficients)