Astudent is trying to solve the system of two equations given below:
equation p: y + z = 4
equation q: 3y + 7z = 15
which of the following steps can be used to eliminate the y term?
a)−3(y + z = 4)
b) 3(y + z = 4)
c)−1(3y + 7z = 15)
d) −3(3y + 7z = 15)

A)−3(y + z = 4)

Step-by-step explanation:

Equation P: y + z = 4  

Equation Q: 3y + 7z = 15  

To eliminate the y term,  The equations have to have the coefficients on y equal and opposite.

Equation Q has 3y, so Equation P needs -3y

Multiply equation P by -3

−3(y + z = 4)

m∠a is 90°

m∠b is 40°

x = 2

step-by-step explanation:

if sr parallel to ba then the sides bc and ac are in proportion, that is

= ← substitute values

= ( cross- multiply )

27x = 6(4x + 1)

27x = 24x + 6 ( subtract 24x from both sides )

3x = 6 ( divide both sides by 3 )

x = 2