Post a New Question

alg2\trig

posted by .

if a3= 17 & a8=37 are terms in annarithmetic sequece, fina a1 & d. the answer is a1=9 & d=4 but i don't understand how they got the answer, please help!

  • alg2\trig -

    term(3) = a + 2d (by definition)
    = 17
    term(8) = a + 7d = 37

    a+7d = 37
    a+2d = 17
    subtract them
    5d = 20
    d = 4
    sub into a + 2d=17
    a + 8 = 17
    d = 9

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Algebra

    Would someone please check these answers?
  2. algebra

    the equation is : - (2x + 3)-(4 + x). Using the distributive property, my friend got the answer -7 - 3x. I have been fiddling with this problem for 3 hours and don't understand how he got this answer. Can someone please thoroughly …
  3. 8th Grade Algebra-Radicals:Answer Check

    Change each decimal to a fraction in lowest terms. 1) 0.4242.... Answer: 14/33 2)0.58 Answer: 29/50 3)0.14 (Repeating sign over both numbers) Answer: 14/99 Write each expression in simplest form. ( means that it is inside a square …
  4. 8th Grade Algebra-Answer Check

    Write each decimal as a fraction in lowest terms. 1. 0.111... Answer: 1/9 2. 0.02 Answer: 1/50 3. 0.7272... Answer: 8/11 4. 0.012012... Answer: 4/333 ?
  5. 8th Grade Algebra: Answer Check #2

    Add or Subtract (Radicals) { this means squared 1.3{2 + 4{2 Answer: 7{2 2. 8{3 + 3{3 Answer: 11{3 3. 7{5 - 3{5 Answer: 4{5 4. 8{2 - 5{2 Answer: 3{2 5. 6{x + 7{x Answer: 13{x 6. 9{y + 3{y Answer: 12{y Multiply 7. -3x^2(4x^2-3x-5) Answer: …
  6. alg2/trig

    I got this question wrong on my test, and I have to correct it :/ How many permutations are there of all the letters in the word "TEXAS" ?
  7. trig

    Write the expression and evaluate. There is only one answer whIch should match the range of the inverse trig function. Sec^-1(-2) I got 2pi/3 could someone tell me if that is right?
  8. chemistry

    1) Starting with 75.00 g of 1-propanol and 75.00 g of PCl 3. Calculate the theoretical yield of 1-chloropropane. 3CH3CH2CH2OH + PCl 3 --> 3CH3CH2CH2Cl + H3PO3 Answer in terms of grams. the answer that i got is 98.12, is this right …
  9. alg2/trig

    The expression a/a-b + b/b-a is equivalent to a) 1 b)-1 c) ab/a-b d)a+b/a^2-b^2 please help!
  10. alg2/trig

    If 4x^2+9=kx, what value of k will produce equal roots?

More Similar Questions

Post a New Question