Abc is a straight line. the length of ab is four times bigger than bc.
ac=75

AB=15 BC=60

Step by step:

AB+BC=AC

AC=75

Plug in AC to the equation: AB+BC=75

BC=4(ab)

Plug in BC into the equation: AB+4(AB)=75

Simplify: 5AB=75

Divide each side by 5: AB=15

BC=4(15)=60

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step-by-step explanation:

system of linear equation

step-by-step explanation:

as given in the data

a= 20 , b= -12

let us suppose that it is a straight line equation

now we know the formula for the system of linear equation

b= ma + c )

here m is slope of a straight line which is equal to formula

m=   (ii)

and here c is a constant

now putting the value of a and b in equation (ii)

m=

m=

putting the value of a,b and m in equation (i) gives us

-12 = + c

-12=-12 + c

adding 12 to both sides

-12 +12 = -12 +12 +c

0 =c

or c=0

as the value of the constant is zero which gives us that it is a linear equation and this order pair satisfies the system of linear equations.