Hi there!
To solve this problem using substitution, we need to set x equal to a value and substitute it into the other equation.
Since
x - 4y = 5,
x = 5 + 4y
3x - 7y = 10
3(5 + 4y) - 7y = 10
15 + 12y - 7y = 10
15 + 5y = 10
5y = -5
y = -1
Now that we know y is -1, we can substitute it back into the equation to find x:
y = -1
x - 4y = 5
x - 4(-1) = 5
x - (-4) = 5
x + 4 = 5
x = 1
So, your answers are x = 1 and y = -1.
Hope this helps!
Answer:
Given: DB = 7.2 cm, AE = 1.8 cm and EC = 5.4 cm and DE || BC.
DB
AD
=
AC
AE
[by basic proportionality theorem which states that if a line is drawn parallel to one side of a triangle the other two sides in distinct points, then the other two sides are divided in the same.
7.2
AD
=
5.4
1.8
AD=
5.4
7.2×1.8
AD=
10
24
⟹AD=2.4cm