Substitution is where we first Isolate one of the unknowns, express it in terms of the other unknown, and replace the isolated unknown with the other unknown in another equation. So that each time we only need to deal with one unknown. I think you'll get a better idea here:
First name these 2 equations with 1 and 2.
4x + 5y = 7 (1)
y = 3x + 9 (2)
Since y is already isolated in (2), so we can skip the isolation step and continue to substitute.
Substitute (2) into (1).
4x + 5(3x+9) = 7
Expand.
4x + 15x + 45 = 7
Group.
19x + 45 = 7
Shift +45 to the other side and turn it into -45.
19x = 7 - 45
19x = -38
Shift x19 to the other side, turn it into /19.
X = - 38/19
X = - 2
Now we solved x already, we can just substitute x= - 2 back to equation (2).
y = 3(-2) + 9
y = - 6 + 9
y = 3
So, the answers are
x = - 2
y = 3
Answer:
<u>3</u><u>z</u><u>^2 + 3z - 6 </u>=0
3
3 (z^2 + z -2) = 0
3(z+2)(z - 1) = 0
z + 2-2 = 0 - 2
z = -2
z - 1 + 1 = 0 + 1
z = 1
Step-by-step explanation:
- factor out the GCF (3) and divide everything by it, and then set it equal to zero.
- since you have a degree of 2, factor it into two binomials that start with the square root of the first term and end with the square root of the second term.
- 3=0 is extraneous solution so we leave it, then we set each binomial equal to zero to solve for z.
note: your solutions is based on the degree or the exponent of the polynomial or the function.
Answer:
22
Step-by-step explanation:
We can write an equation:
(7+13+10+x)/4=13
x represents the number that needs to be added to get an average of
(7+13+10+x)/4=13
(30+x)/4=13
30+x=52
x=22
The number is 22
Hope this helps! Have a wonderful day :)
Answer:
$17.01
Step-by-step explanation:
To find the the price, you must find price per pound x how many pounds you will be priced for
price per pound x how many pounds you will be priced for
This is represented by 3.78 x 4.5
3.78 x 4.5 = 17.01
$17.01 is the cost of 4.5 pounds of almonds
Answer: 38 is your answer hope this helped
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Step-by-step explanation: