Помогите!!!! 7x+9=100 26x-0,8=7

Question

Помогите!!!!
7x+9=100
26x-0,8=7

Answer 1

7х=100-9, 7х=91, х=91:7, х=13
26х=7+0.8, 26х=7.8, х= 7.8:26, х= 78:260, х= 0.3