Multiply everything in the parenthesis by a.
ac + ab = d
Subtract ab from both sides.
ac = d - ab
Divide a on both sides.
c = d - ab / a
Hope this helps!
42789 times 54678
is 2,339,616,942
Show Work:
<span>Calculate 9 x 8, which is 72.
Since 72 is two-digit, we carry the first digit 7 to the next column.
</span>
3 <span>Calculate 8 x 8, which is 64. Now add the carry digit of 7, which is 71.
Since 71 is two-digit, we carry the first digit 7 to the next column.
</span>
4 <span>Calculate 7 x 8, which is 56. Now add the carry digit of 7, which is 63.
Since 63 is two-digit, we carry the first digit 6 to the next column.
</span>
5 <span>Calculate 2 x 8, which is 16. Now add the carry digit of 6, which is 22.
Since 22 is two-digit, we carry the first digit 2 to the next column.
</span>
6 <span>Calculate 4 x 8, which is 32. Now add the carry digit of 2, which is 34.
Since 34 is two-digit, we carry the first digit 3 to the next column.
</span>
7 <span>Bring down the carry digit of 3.
</span>
8 <span>Calculate 9 x 7, which is 63.
Since 63 is two-digit, we carry the first digit 6 to the next column.
</span>
9 <span>Calculate 8 x 7, which is 56. Now add the carry digit of 6, which is 62.
Since 62 is two-digit, we carry the first digit 6 to the next column.
</span>
10 <span>Calculate 7 x 7, which is 49. Now add the carry digit of 6, which is 55.
Since 55 is two-digit, we carry the first digit 5 to the next column.
</span>
11 <span>Calculate 2 x 7, which is 14. Now add the carry digit of 5, which is 19.
Since 19 is two-digit, we carry the first digit 1 to the next column.
</span>
12 <span>Calculate 4 x 7, which is 28. Now add the carry digit of 1, which is 29.
Since 29 is two-digit, we carry the first digit 2 to the next column.
</span>
13 <span>Bring down the carry digit of 2.
</span>
14 <span>Calculate 9 x 6, which is 54.
Since 54 is two-digit, we carry the first digit 5 to the next column.
</span>
15 <span>Calculate 8 x 6, which is 48. Now add the carry digit of 5, which is 53.
Since 53 is two-digit, we carry the first digit 5 to the next column.
</span>
16 <span>Calculate 7 x 6, which is 42. Now add the carry digit of 5, which is 47.
Since 47 is two-digit, we carry the first digit 4 to the next column.
</span>
17 <span>Calculate 2 x 6, which is 12. Now add the carry digit of 4, which is 16.
Since 16 is two-digit, we carry the first digit 1 to the next column.
</span>
18 <span>Calculate 4 x 6, which is 24. Now add the carry digit of 1, which is 25.
Since 25 is two-digit, we carry the first digit 2 to the next column.
</span>
19 <span>Bring down the carry digit of 2.
</span>
20 <span>Calculate 9 x 4, which is 36.
Since 36 is two-digit, we carry the first digit 3 to the next column.
</span>
21 <span>Calculate 8 x 4, which is 32. Now add the carry digit of 3, which is 35.
Since 35 is two-digit, we carry the first digit 3 to the next column.
</span>
22 <span>Calculate 7 x 4, which is 28. Now add the carry digit of 3, which is 31.
Since 31 is two-digit, we carry the first digit 3 to the next column.
</span>
23 <span>Calculate 2 x 4, which is 8. Now add the carry digit of 3, which is 11.
Since 11 is two-digit, we carry the first digit 1 to the next column.
</span>
24 <span>Calculate 4 x 4, which is 16. Now add the carry digit of 1, which is 17.
Since 17 is two-digit, we carry the first digit 1 to the next column.
</span>
25 <span>Bring down the carry digit of 1.
</span>
26 <span>Calculate 9 x 5, which is 45.
Since 45 is two-digit, we carry the first digit 4 to the next column.
</span>
27 <span>Calculate 8 x 5, which is 40. Now add the carry digit of 4, which is 44.
Since 44 is two-digit, we carry the first digit 4 to the next column.
</span>
28 <span>Calculate 7 x 5, which is 35. Now add the carry digit of 4, which is 39.
Since 39 is two-digit, we carry the first digit 3 to the next column.
</span>
29 <span>Calculate 2 x 5, which is 10. Now add the carry digit of 3, which is 13.
Since 13 is two-digit, we carry the first digit 1 to the next column.
</span>
30 <span>Calculate 4 x 5, which is 20. Now add the carry digit of 1, which is 21.
Since 21 is two-digit, we carry the first digit 2 to the next column.
</span>
31 <span>Bring down the carry digit of 2.
</span>
32 <span>Calculate 342312 + 2995230 + 25673400 + 171156000 + 2139450000, which is 2339616942</span>
<span> </span>
