What is the unknown number ( +4)+59=70 i think it is 7

it is 7 youre correct

there are infinitely many solutions.

m∠5 + m∠3 = m∠1   is true.

m∠5 + m∠6 = 180 is true

m∠2 +m∠3 = m∠6   is true

m∠2 +m∠3 +m∠5 = 180   is true