If the following systerm of equations was written as a matrix equation in the
a=[a c]
[b d]
form ax =c and matrix a was expressed in the form, find the value of a-b+c+d
2x + 8y=7
4x- 2y= 9

step-by-step explanation:

if you want to solve percent error follow these steps.

1. subtract the accepted value from the experimental value.

2. take the absolute value of step 1.

3. divide that answer by the accepted value.

4. multiply that answer by 100 and add the % symbol to express the answer as a percentage.

if you want to solve percent of change just do this.

1. work out the difference (increase) between the two numbers you are comparing.

2. divide the increase by the original number and multiply the answer by 100. if your answer is a negative number then this is a percentage decrease.

hope this : )

the answer is b. 60. each interior angle in 120, so the exterior angle must be 60 in order to add up to 180

step-by-step explanation:

stethere all not eveanp-by-step explanation:

step-by-step explanation:

the true ones are a b and d