The formula to find the perimeter of a rectangle is P= 2(l+w). By substituting what we now knowin to the equation:
•42=2(l+(2/5l)). We can have width represented at (2/5l) because it’s now 2/5 of the length. Now add them together to get a single coefficient for l.
•42= 2(7/5l). Multiplying 7/5 by 2.
42= (14/5l). Multiplying both sides by the reciprocal of 14/5, which is 5/14, to get l by itself.
•l= 15.
Now that we now know the value of l, we know that the length is 15m. To find the width of the answer, we then multiply 15 by 2/5, which equals 6. Therefore, the only third option is correct because the length is 15m and the width is 6m.
First, the factor pairs for 18 are:
1, 18
2, 9
3, 6
Since the middle term is -3, the two factors must be 3 apart. The only pair that is 3 values apart is 3, 6.
Since the middle value is negative, the larger number is negative. This means that the 6 is negative.
z = -6
z = 3
Set each equal to 0;
z = -6
z + 6 = 0
z = 3
z - 3 =0
So your factors are (z+6) and (z-3), or answer B.
B) 29
Because 20^2+21^2=c^2