Which ordered pair in the form (a, b) is a solution of this equation?

3a – 4b = 21

A.
(–3, –2)

B.
(0, 7)

C.
(–2, –3)

D.
(7, 0)


Sagot :

3(7)-4(0)=21
3*7=21-0=21
the answer is D
substitute the first number in the (  ) for a and the second for b
3(-3)-4(-2)
-9+8 does not =21

B.  3(0)-4(7)
0-28 does not = 21

C.  3(-2)-4(-3)
-6+12 does not =21

D. 3(7)-4(0)= 21 yeah

answer is D (7,0)

hope this helps