How do I solve this fraction question?If a = − 1 / 5, how do I calculate: 3 a + 2 a 2 I did 3 × ( − 1 / 5 ) + ( − 1 / 5 ) × ( − 1 / 5 ) × 2, but can't figure out what the right way to solve this is.

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How do I solve this fraction question?If   a  =  −  1      /    5, how do I calculate:  3  a  +  2      a    2  I did   3  ×  (  −  1      /    5  )  +  (  −  1      /    5  )  ×  (  −  1      /    5  )  ×  2, but can&#039;t figure out what the right way to solve this is.

Immanuel Brennan · Accepted Answer

A helpful tip: You can only add fractions with the same denominator (the numbers at the bottom). If the denominators are not equal, you have to multiply them by a constant number   k to add them.Starting from            3      ×      −      1        5    +            −      1      ×      −      1      ×      2              5      ×      5        ,since   +  a  ×  −  b  =  −  a  b, and   −  a  ×  −  b  =  a  b for arbitrary numbers   a  ,  b, we have:  −      3    5    +      2    25  Since       1    5   is   5 times that of       1    25  ,   k  =  5, and we have to multiply both numerator and denominator by   5 to simplify:  −      15    25    +      2    25  Now you can simplify the expression by cancelling       10    25   and adding the   2 fractions together:  −      15    25    +      2    25    =            −      15      +      2        5  I&#039;ll leave the last step for you to figure out.

Martin Hart · Accepted Answer

That&#039;s the correct way.                              (          3          ×                                    −              1                        5                    )                +                  (                                    −              1                        5                    ×          2          ×                                    −              1                        5                    )                                    =                              −            3                    5                +                  2          25                                                  =                              −            15                    25                +                  2          25                                                  =                              −            13                    25

How do I solve this fraction question? If a=−1/5, how do I calculate: 3a+2a^2 I did 3xx(−1/5)+(−1/5)xx(−1/5)xx2, but can't figure out what the right way to solve this is.

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