Answer:
4 and -4 are both the square roots of 16
Step-by-step explanation:
4.2x - 1.4y = 2.1 |multiply both sides by 10
42x - 14y = 21 |subtract 42x from both sides
-14y = 21 - 42x |change signs
14y = 42x - 21 |divide both sides by 14
y = 3x - 1.5
A^2+b^2= c^2
3^2+4^2=c^2
9+16=c^2
25=c^2
5=c
