This animation walks through finding unknown coefficients a and b in a pair of linear equations, given that the solution point (3, -1) satisfies both. It shows step-by-step substitution into each equation, isolating the unknown, and solving simple linear equations to get a = -2 and b = 2, then computing a - b = -4. Useful for students practicing substitution techniques and verifying solutions to systems of linear equations.
Narrated · 16:9 · Preview before teaching · automatic layout checks do not establish subject accuracy
Pembahasan Soal Sistem Persamaan Linear Diketahui sistem persamaan: 3x+ay=11 bx-2y=8 Dengan solusi (x,y)=(3,-1). Langkah 1: Menentukan nilai a Substitusikan x=3 dan y=-1 ke persamaan pertama. 3(3)+a(-1)=11 9-a=11 -a=2 \boxed{a=-2} Langkah 2: Menentukan nilai b Substitusikan x=3 dan y=-1 ke persamaan kedua. b(3)-2(-1)=8 3b+2=8 3b=6 \boxed{b=2} Langkah 3: Menghitung a-b a-b=-2-2 \boxed{a-b=-4} Jadi, jawaban yang benar adalah C. -4.