Answer:
Tổng 3 góc trong 1 tam giác là 180 độ
Vậy góc B = 180 - A - C = 180 - 90 - 50 = 40 độ
Answer:
x=7 because 25-4=21 and 21 ÷3=7
Answer:
yus can you answer this for me
Step-by-step explanation:
21
E (225-25n)
n=1
So its D.
Answer:
Step-by-step explanation:
(x+3)² -5 =0 , use the formula (a+b) ² = a²+b²+2ab
x²+9 +6x -5 =0 , combine like terms
x²+6x +4 =0, use the quadratic formula x = (-b±√b²-4ac)/2a
x= (-6 ±√6²-4*1*4)/2*1
x= (-6 ± √36-16) /2
x= (-6±√20)/2
x=(-6 +2√5)/2 and x=( -6-2√5) /2, factor 2 in the numerator and simplify
x= -3 +√5 and x= -3 -√5
