Question

pfv quem conseguir resolver me responda

Answer 1

a) (x+3)² = 49
x²+2.x.3+3² = 49
x²+6x+9 = 49
x²=49-9-6x
x²= 40-6x
x= √(40-6x)
b) (5x-4)² = 9
5x²-2.5x+4² = 9
5x²-10x+16 = 9
5x²= 9+10x-165x²= 10x-7
x²=(10x-7)/5
x²=2x-7
x= √(2x-7)

c) (21x-7)² = 0
21x²-2.21x.-7+7² = 0
21x²+294+49=0
21x²+343=0
x²= -343/21
x²= -16,333
x= √-16,333
x = não existe.