How do you add $\frac { 7} { - 2} + \frac { 2} { 5}$ ?

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Answer 1 · 2017-08-11T01:20:36

See a solution process below:

First, rewrite the expression as:

$-7/2 + 2/5$

Now, we need to put the fractions over a common denominator by multiplying each fraction by the appropriate form of $1$ :

$(5/5 xx -7/2) + (2/2 xx 2/5) =>$

$(5 xx -7)/(5 xx 2) + (2 xx 2)/(2 xx 5)$

$-35/10+ 4/10$

We can now add the two numerators over the common denominator:

$(-35 + 4)/10 =>$

$-31/10$

Answer 2 · 2017-08-11T01:28:47

$-31/10$

Find the LCD:

We can write out the factors of both $2$ and $5$ to determine this.

$2: 2, 4, 6, 8 , color(red)10$
$5: 5, color(red)10, 15$

The LCD is thus $10$ , therefore:

$[-7/2(5/5)]+[2/5(2/2)] larr$ **We manipulate the fractions in such a way that the denominator is 10 **

$-35/10+4/10$

$=-31/10$

How do you add \frac { 7} { - 2} + \frac { 2} { 5}\frac { 7} { - 2} + \frac { 2} { 5}?