Step 1) Subtract #color(red)(5)# from each side of the equation to isolate the #r# term while keeping the equation balanced:
#-7 - color(red)(5) = 4/3r + 5 - color(red)(5)#
#-12 = 4/3r + 0#
#-12 = 4/3r#
Step 2) Multiply each side of the equation by #color(red)(3)/color(blue)(4)# to solve for #r# while keeping the equation balanced:
#color(red)(3)/color(blue)(4) xx -12 = color(red)(3)/color(blue)(4) xx 4/3r#
#color(red)(3)/cancel(color(blue)(4)) xx -color(blue)(cancel(color(black)(12)))3 = cancel(color(red)(3))/cancel(color(blue)(4)) xx color(blue)(cancel(color(black)(4)))/color(red)(cancel(color(black)(3)))r#
#3 xx -3 = r#
#-9 = r#
#r = -9#
