Solve the simultaneous equations: (1) y – 2x – 4 = 0 , (2) 4x^2 + y^2 + 20x = 0

Rearrange (1): y=2x+4

Subsitute this into (2): 4x2+(2x+4)2+20x=0

Simplify and collect like terms: 8x2+36x+16=0

Factorise: (2x+1)(x+4)=0

Therefore: 2x+1=0 -> x=-0.5  and x+4=0 -> x=-4

Substitute this into (1) to get values for y: y=3 and y=-4

AT

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