It is true. here is how........
4-0 is rounding down
5-9 is rounding up
when rounding to the tenths place you look at the hundredths place to find the answer.
Try using
Wolframalpha.com
It can solve any mathematical problem
see the attached figure to better understand the problem
we know that
1) If angle 1 and angle 2 are complementary angles
then
m∠1+m∠2=
------> equation A
2) If angle 1 and angle 2 are congruent angles
then
m∠1=m∠2 ------> equation B
Substitute equation B in equation A
m∠1+(m∠1)=
2m∠1=
m∠1=
therefore
<u>the answer is</u>