Solve the problem in the picture please

Mathematics

1 answer:

Salsk061 [2.6K]3 years ago

5 0

(1) y= - x² - 4x + 9 and (2) y + 5x = - 7. Isolate y in (2); y= - 5x - 7 (3)

Since (1) and (3) have the same value or the same y, then we can write:
(1)=(3)

- x² - 4x + 9 = - 5x - 7

-x² - 4x + 9 + 5x +7 = 0

-x² + x + 16 = 0 OR x² - x - 16 = 0

Solve this quadratic equation:

x' = [-b+√(b²-4ac)]/(2a) and x" = [-b-√(b²-4ac)]/(2a)

x' = [+1+√(-1)² - 4(1)(-16)]/2 → x' = [1+√(1+64)]/2 → x' = [1+√65)]/2
x" = [+1-√(-1)² - 4(1)(-16)]/2 → x' = [1-√(1+64)]/2 → x' = [1-√65)]/2

x' = [1+√65)]/2 = + 4.5311

x" =[1-√65)]/2 = - 3.5311

You might be interested in

I NEED HELP ASAP!!!!!

Y_Kistochka [10]

The only solution is x=7
Although the problem is solves correctly, always makes sure to check it by inputting it back into the equation. Putting -3 into the equation, one side turns negative and the other is positive. For this reason, it is impossible for one of the answers to be -3.

6 0

1 year ago

What addition doubles fact can help you solve 4 +5?

goldfiish [28.3K]

4 + 4 can help. Then add one.

4 0

2 years ago

Read 2 more answers

A construction crew must build 4 miles of road in one week. On Monday, they build 12 mile of road. On Tuesday, they build 13 mil

Julli [10]

$\frac{19}{6}$ many more miles of road are left to build .

<u>Step-by-step explanation:</u>

Here we have , A construction crew must build 4 miles of road in one week. On Monday, they build 1/2 mile of road. On Tuesday, they build 1/3 mile of road. We need to find that How many more miles of road are left to build . Let's find out: