Rational im pretty sure from what i remember
        
             
        
        
        
Answer:

Step-by-step explanation:
1) if to re-write the given equation into slope-interception form, then:

the slope of the given line is 5/2;
2) according to the rule of perpendicular, the required slope should be:
s*(5/2)=-1;
3) if to solve this equation (s*5/2=-1), then s=-2/5 or -0.4.
 
        
             
        
        
        
Answer:
$18.36
Step-by-step explanation:
In this question, we have to find the cost of the cake for the customer who orders a month early.
We know that the original price of the cake is $30.
We also know that there was a 28% discount and a 15% discount added to the purchase.
Remember, You don't add discount percentages together, you discount the prices separately.
Solve:
First, apply the 28% discount.
30 · 0.28 = 8.40
30 - 8.40 = 21.60
Now apply the 15% discount to the new price.
21.60 · 0.15 = 3.24
21.60 - 3.24 = $18.36
They needed to pay $18.36 for the cake.
 
        
             
        
        
        
When you have something like this, all you need to do is substitute the values, the last is for what value of x
For the first one;
((x^2+1)+(x-2))(2)
(x^2+x-1)(2)
(2)^2+(2)-1
4+2-1
5
For the second one;
((x^2+1)-(x-2))(3)
(x^2-x+3)(3)
(3)^2-(3)+3
9-3+3
9
For the last one;
3(x^2+1)(7)+2(x-2)(3)
3((7)^2+7)+2((3)-2)
3(49+7)+2(3-2)
3(56)+2(1)
168+2
170