Answer:
x = 12, y = 20
Step-by-step explanation:
Given
4a - 2b
= 4[tex]\left[\begin{array}{ccc}4\\7\\\end{array}\right][/tex] - 2[tex]\left[\begin{array}{ccc}2\\4\\\end{array}\right][/tex] ← multiply each component by the scalar
= [tex]\left[\begin{array}{ccc}4(4)\\4(7)\\\end{array}\right][/tex] - [tex]\left[\begin{array}{ccc}2(2)\\2(4)\\\end{array}\right][/tex]
= [tex]\left[\begin{array}{ccc}16\\28\\\end{array}\right][/tex] - [tex]\left[\begin{array}{ccc}4\\8\\\end{array}\right][/tex] ← subtract corresponding components
= [tex]\left[\begin{array}{ccc}16-4\\28-8\\\end{array}\right][/tex]
= [tex]\left[\begin{array}{ccc}12\\20\\\end{array}\right][/tex] = [tex]\left[\begin{array}{ccc}x\\y\\\end{array}\right][/tex]
with x = 12 and y = 20
