Very basic and novice mathematical problems A * b = 144 and a = 2B

Very basic and novice mathematical problems A * b = 144 and a = 2B

Because a = 2B
So a * b = the square of 2B = 144
So B = 6 radical 2 or B = - 6 radical 2
So a = 12 radical 2 or a = - 12 radical 2

A very novice mathematical problem
In Δ ABC, angle A: angle B: angle c = 1:1:2, a, B, C are angles a: angle B: opposite side of angle c, then ()
A：b2+c2=a2； B：C2=3b2；
C:3a2=2c2； D：c2=2b2；

From angle A: angle B: angle c = 1:1:2, the isosceles right triangle is obtained,
So a = B,
So C ^ 2 = a ^ 2 + B ^ 2 = 2B ^ 2
Choose D

Is 1500 a common multiple of 4 and 7?

Of course not. 1500 is not divisible by 7