Solve the simultaneous equations 5x + 3y = 24 and 3x - 4y = 26
Ok, so here are the equations5x+3y=243x-4y=26So let's multiply the first equation by 3, which gives us:15x+9y=72Now let's multiply the second equation by 5, which gives us:15x-20y=130So we're now left with:15x+9y=7215x-20y=130Let's rearrange both of these equations to make 15x the subject. So now we're left with:15x = 72-9y15x= 130+20yNow we can compare these two equations, to give us:72-9y=130+20y (=15x)If we rearrange this new equation, we find that:20y + 9y = 72 - 13029y = -58y = -2Since we now have a value for y, we can substitute this back into 5x + 3y = 245x + 3(-2) = 245x -6 = 245x = 30x = 6So, are final answer is x = 6 and y = -2
WS
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