Answer:
the solutions are 0 and 7
Step-by-step explanation:
4r²-28r=-49 take out the 4 to make it a simple trinomial
4(r²-7r)=-49 find half of 7 and square it
4(r²-7r+12.25)=-49 now factor
4(r-3.5)²=-49 divide by 4
(r-3.5)=-12.25 now square root bother sides
r-3.5=+/-3.5 add 3.5
r=3.5+3.5 =7
r=-3.5+3.5=0
