<em>Answer:</em>
<em>7/78 - 35/78i</em>
<em>Step-by-step explanation:</em>
<em>A complex number is a real number, an imaginary number or a number with both real and imaginary number. Its standard form is:
</em>
<em>a + bi
</em>
<em>
</em>
<em>For the expression, 7/ 3-15i
</em>
<em>
</em>
<em>(7/ 3-15i) (3+15i)
</em>
<em>21 - 105i / (234)
</em>
<em>7/78 - 35/78i
</em>
(2x+1)(x-2) = 2x^2 - 4x +x -2= 2x^2-3x-2
3. We can see that
1+100=101
2+99=101
3+98=101
.................
and so on
From 1 to 100, there are 50 pairs that has the sum is 101
Z=101×50=5050
4. We can see that
1-2=-1
3-4=-1
5-6=-1
...........
and so on
There are 10 pairs that has sum is -1
Z= 10×(-1)=-10