At a fabric store, fabrics are sold by the yard. A dressmaker spent $36.35 on 4.25 yards of silk and cotton fabrics for a dress. Silk is $16.90 per yard and cotton is $4 per yard. Find the solution of the system of equations. Explain or show your reasoning
{x+y=4.25} ; {16.90x+4y=36.35}

The yards of silk bought is  1.49 yards and the yard of cotton bought is 2.76 yards.

The two equations are known as simultaneous equation. They would be solved using elimination method.

x + y  = 4.25 equation 1

16.90x + 4y = 36.25 equation 2

where:

x = yards of silk bought

y = yards of cotton bought

In order to determine the value of x, multiply equation 1 by 4.

4x + 4y = 17 equation 3

Subtract equation 3 from 2

19.25 = 12.90x

Divide both sides of the equation by 12.90

x = 1.49 yards

In order to determine the value of y, substitute for x in equation 1

1.49 + y = 4.25

y = 4.25 - 1.49

y = 2.76 yards

To learn more about simultaneous equations, please check: link

The number of yards of silk = x = 1.5 yards

The number of yards of cotton = y = 2.75yards

Step-by-step explanation:

At a fabric store, fabrics are sold by the yard. A dressmaker spent $36.35 on 4.25 yards of silk and cotton fabrics for a dress. Silk is $16.90 per yard and cotton is $4 per yard.

Find the solution of the system of equations. Explain or show your reasoning

{x+y=4.25} ; {16.90x+4y=36.35}

Let the number of yards of silk = x

The number of yards of cotton = y

We are given the system of equations:

{x+y=4.25} Equation 1

x = 4.25 - y

{16.90x+4y=36.35} Equation 2

4.25 - y for x in Equation 2

16.90(4.25 - y) + 4y = 36.35

71.825 - 16.90y + 4y = 36.35

71.825 - 36.35 = 16.90 - 4y

35.475 = 12.90y

y = 35.475/12.90

y = 2.75 yards.

The number of yards of cotton = y

{x+y=4.25} Equation 1

x = 4.25 - y

x = 4.25 - 2.75

x = 1.5 yards

The number of yards of silk = x = 1.5 yards

answer: c.  

step-by-step explanation:

mixtures containing substances that get attracted to magnet can be separated using a magnet. we can separate iron from a mixture of sand and iron, as only iron attracts to the magnet.

1) the property is   ixi = a ⇔x = a   o x = -a

4(x-5)+3= 15⇒4x-20+3 = 15⇒4x-17= 15⇒4x = 15+17⇒4x = 32⇒x =32/4= 8

4(x-5) +3= -15⇒4x-20 +3 = -15⇒4x-17= -15⇒4x =-15+17⇒4x = 2⇒x =2/4= 1/2

the values are x =8 and x = 0,5